I have refrained purchasing newer games by publishers like Ubisoft/ Rockstar/ EA because of their mandatory launcher/ account thing, in addition to using Steam.

I was wondering whether the same restrictions do apply to console versions of games. Like, do I need to use Rockstar Launcher/ Ubisoft Connect if I decide to play a singleplayer game on Playstation, for example?

Thanks in advance.

No

When I bought Assassins Creed Valhalla for the PS4, it wouldn't let me play the game until I logged in to their Ubisoft Connect service.
Maybe the main menu was temporarily bugged (Ubisoft games are almost always in a horrendous state during their first few months), but I had to connect my account. Haven't touched the game since beating it, so I wouldn't know if that issue still exists.

No it is not, but still the game is a clown fiesta

No, at least from my experience.
I was not into console gaming until recently, but I do enjoy it occasionally.

No it is not. It is only a punishment for PC gamers. I have AC Odyssey on PS4 (great game by the way) purely because of the ubishite launcher, but for that you get noticeably reduced graphics (PS4 is very weak compared to my PC) and limited to HD, no widescreen. Is that worth not having the launcher, yes, trying is better than all these launchers and clients scamming your data and dumbing down even simple tasks.

Because everything now has its own client launcher, you could install galaxy and use that to launch steam, and then from the launch uplay and finally even, maybe, lay the product although your computer will likely blow up leaking all your data out.

I hear you, I enjoyed Odyssey despite its repetitive nature, for some reason. I avoided the PC version as I can't be bothered with launchers and all that tripe. I wouldn't call it great, but it was fun overall.

Yep, it had some ship action which origins lacked. Also a huge map, although it was two or three things copy pasted across it. However sit on one of the giant statues and look out over the sea with the biremes to the setting sun whilst small Greek settlements glow n the distance is something to wonder at. Just like origins had some nice vistas, and Valhalla as well.

This might sound odd, but overall I prefer Origins over Odyssey, naval segments included. What Odyssey does better, by far, is combat, in my opinion. Also, some vistas are outstanding in Odyssey. With that being said, I feel Odyssey also offers better DLCs. I was disappointed with Fields of Elysium, but I loved Torment of Hades. The Fate of Atlantis was decent enough, I guess. On the other hand, I had to force myself through The Hidden Ones in Origins. The Curse of the Pharaohs was better, but that's not saying much.
I've so many videos and screenshots from Odyssey... I had to go back and fight the Hekatonchires again. Good times.

No. Consoles are far simpler in that regard. Games are kind of restricted by console but there is no additional software needed to download and run a game on console in that regard.

There isn’t any need for “additional software” to download and run a game on PC. For many decades software has been sold as files which you can install offline, no client or launcher needed. What a client is there for is to, n a lot of cases, control your access to your product, and milk your data, whilst providing a closed monopolised environment for things like microtransactions. Any additional functionality given is pretty pointless, online saves for those who can’t copy and paste their own files, achievements for those people with no hope in life, time tracking??, and that’s really about it.

...a store built-in, so you can purchase more games from the company. For those too lazy to open up a proper web browser and purchase said games from the actual web store itself...

No, but sometimes yes anyway.

For example, Need for Speed Hot Pizza (Criteron) will nag me to create an account or sign in because of the multiplayer.

I started Far Cry 6 on PS5 the other day, and I was prompted with a Uplay sign in screen, but I think you can skip it and play "offline". There is no need to install any extra apps though.