I got into it because I got Total War Napoleon (another annoying launcher with the Total War series nowadays…) and didn't realize beforehand that you needed an Steam account for it.
I came around to appreciate the storefront and library for my purchased digital games. But as you said, I don't want to have to run a nanny program to play my games. Especially my single player games.
That's what I like about gog though, I can just download an offline installer for my games from them. Although I think by now even they have games on their store that require launchers.