why I even bother.

There's a voting system to help draw attention to games that you want on GOG. That might help.
I understand it is insane replying to a comment from almost 3 years like this but I came here specifically looking for Hellcard on GOG instead of steam myself.

The studio was supposed to develop like 7 games, which all could be installed and played from a common hub-interface.
I suspect the studio sold vapourware with that concept.

Uh what? They are still releasing games on Steam are they not?

They are definitely notm releassing anything on GoG though.
So if they are developing them and releasing on Steam - why not on GoG? Why should I go to the suggestion-biox to vote on some CURRENT game, when the box is for old games the first place?

You are making no sense. And the whole situation is fishy.

I want them to release their games on GOG as well. I do not understand how that makes the company fishy though. It sounds like they are just not interested in/prioritizing releasing on GOG

So they brought the 1st game, and all the promises of the future games, then they don't dleiver the future games.
That's fishy in my book.

Developer's response on Steam forum

Edit:
Okay for some reason I can't attach a screenshot so here's a quote: "Hellcard uses Steam Networking for co-op, so it won't be available on GOG until we migrate to a different solution. We plan to do that but not before Early Access is over."

And here's update from 3 days ago: "Still working on a platform-agnostic backend. It's been partially implemented (some of the newer co-op bugs are due to the work on the backend, actually)."

Thanks!