Why all my submitted isssues weren't answered? Look at the date. The oldest is over 50 days old and still no response. When do you plan to end this beta?

Also I noticed that qp0n isn't very active when it comes to issues that system assigns. (all of my entries were automatically assigned to qp0n)

I think they just get really a lot of reports there and might focus on more important ones.
Also looking at some of your reports, there is some stuff easily explained:

You have to install the launchers you connect (it even says that in the galaxy 2.0 faq). Just because it might work fine with Origin, doesn't mean it'll work like that with other integrations like battle.net.

Also for problems with integrations, it might be a good idea to report this directly to the creators of the plugin instead of gog stuff, which are most likely just forwarding these issues anyway. For battle.net look here: https://github.com/FriendsOfGalaxy/galaxy-integration-battlenet/issues
They explicitly say that you should report problems about classic blizzard games to them, quote:

edit: removed because I think it's a different problem. Anyway, I think, for classic blizzard problems, just ask on github and you probably get a much faster answer.

For the not updating art: Galaxy does not use SteamDB, so it won't update any art like it does on Steam (I mean, galaxy uses different proportions, so it wouldn't work anyway). If you got some nice art you wanna use, you can either just edit the galaxy entry of the game manually or, if you got official artworks, you might try to change the igdb.com entry, as it seems like galaxy 2.0 is at least partly using that data base.

I think that all integrations crashing together is pretty important to fix. But that's stupid. What if in the future I would like to install only GOG GALAXY on my new device and all my integrations are crashing just because I don't have the launchers. I don't even have the games installed from other shops, just Steam and GOG. It should work without. It was when B.net plugin was still a part of galaxy and not a community plugin. I don't know how Galaxy work with that. It would be great to use the pictures from Steam when you link the accounts. Different platforms can have different art.

But as neither this forum nor mantis is flooded with a lot of people having your problem, most probably means that this is a problem tied specifically to your setup. Which does not make it irrelevant but may have an impact on its priority.
And If you have a look at the dashboard page you can see that they are indeed working on a lot of tickets - currently the dashboard states that they were working on roughly 1500 tickets in the last 30 days

Overall I have the feeling you are missing the point of the beta phase. This isn't production ready and there was never a specific date announced when it will leave that phase - maybe this happens next week, maybe no sooner then six months - who knows... Then I suggest you buy only games on gog as only then you can be 100% sure you won't need any additional launcher. In most cases games from DRMed game services need their launcher, so you can't expect from gog that it waves a magic wand to make them work regardless of whether they are tied to client. Yes, but they will only use their own database as source for data relevant for a game. Which makes a lot of sense as this would mean a lot of people would have a lot of different experiences with their library, which in turn would lead to a much more complicated situation to unravel in case an error is reported.

Well, maybe somebody in the future will install Galaxy on same setup so it should be at least worth looking at logs right? I'm not talking that they don't work on anything at all. I'm talking that they didn't even bother to look at my entries. But that doesn't matter now because they finally responded. Coincidence? I'm not missing the point. I know that the beta can be full of bugs or even not working at all, but the point is to learn why it doesn't work so you must at least gather the logs. Look. I linked my account so in theory I will be able to have a look at my connected library on a website. Do I need other launchers to just view my library? I'm not playing them, I'm not even installing them. Again, I'm not playing or installing every game from every launcher. And yes, I expect it to work because it is marketed as a One True Launcher for every other launcher. So asking for what I'm asking isn't so irrational. What about games that aren't on GOG? Steam right now is full of games not available on GOG. Also Epic, Origin. I'm pretty sure that different cover images aren't exactly worthy of being described as a lot o different experiences. And definitely it won't lead to critical errors.

You know, there are also games not on steam. If they rely on the SteamDB, what about those? And the gog database does not only contain games they sell on their store, like I said previously, they are using igdb.com, I guess a customized version of it. I think it makes a lot of sense to use an independent database instead of clinging all the launchers stuff together, especially with games that are on multiple launchers.It would be a mess if those all had multiple meta data depending on the launcher. Also, still, steam uses images that are aligned horizontally while galaxy uses images that are aligned vertically (like CD covers), how would that work? It would be a ton of work to adjust instead of just using another database and fix the few faulty ones.
So if you really wanna use updated art so badly, just edit them yourself.

Simple, use another database. What's stopping them from using more than one? Agree, but we're still talking only about images. Well, wouldn't you know that Valve plans to redesign Steam to use vertical images (like CD covers) in new update. So it would literally just be copy paste job.
https://steamcommunity.com/groups/steamworks/announcements/detail/1597002662762032240 Few maybe, but my library alone has 67 games that are missing the cover image and there are even more that don't have the special vertical cover art. One option would solve big number of them and work in the future. Other option would require to manually fix every game and not solve any future problems. I want the GOG Galaxy 2.0 to be a good software. Good software doesn't involve making everything manually. And is it that bad that I want it to look good? The updated art that I was talking about in my submitted issue was in fact vertical cover art that was submitted to Steam few hours after I got my beta invitation and saw that the game doesn't have the compatible art. I assumed that it uses images submitted to Steam when connecting Steam account because what other would it use?

Yes, thats why I wrote "Which does not make it irrelevant but may have an impact on its priority" No that is simply not true, they where already asking for more information at least in one ticket What are you talking about, they integrated a bug report feature that appends log in their application, and even asked you specifically for a certain log file. Sorry, my bad, from the ticket I figured that you wanted to install games, not only view the available games for that account. While they specifically target that question in the faq section of the Galaxy page, it should be communicated more clearly on that page. Who said that their database only contains games that are available on gog? The point is that this guarantees that there is only a single point of failure for that certain aspect, which is always great. There is also the problem, that this would also mean that users would need a way to choose which image source they favour, which is also something that needs to be implemented and is a possible point of failure (while they are still trying to be equal in features with the old client). And additionally this gives them the ability to see for which games their database still needs work.

It is true. Before I made this topic ONLY ONE of my submitted issues had replies. And it wasn't even the person that the issue was assigned to. The logs aren't always added automatically. And they asked for a certain log file once.

I'm dropping the discussion on using multiple databases because we clearly have different opinions.

This topic was made because my issues weren't answered or even looked into for more than 50 days. Coincidentally few of them were answered and one even was solved after I made this topic. Still few remain not answered and nobody replied to collect more data. (such as games that are missing cover images (or maybe even background and icon, but I can only see cover images easily)).
Also qp0n started to be active again, but made an oopsie - https://mantis2.gog.com/view.php?id=6473. (didn't understood the topic problem and closed it)