This might be a bit confusing and hard to follow so I'll give you an example.

I have Rainbow Six Siege on Steam. However, as you know - playing Ubisoft games on other launchers does also launch Uplay. Playing this game through Steam and quitting out with the "Automatically Close Down Launcher after Quitting the Game" option. Only closes down Steam, not Uplay.

I'm wandering if that would be even possible for the developers to do that considering that Uplay isn't the launcher that was selected to start the game.