For community, there’s tons of different communities for every game and Steam is usually one of the least active anyways.
For mods, as far as I know there’s no exclusivity there. In fact, it’s kind of a pain to mod Bethesda games because they don’t go through Steam. It’s similar to DLC in that it’s just a better experience to have mod support included in the launcher.
For the launcher, that seems like once again a huge blow to consumers to have a separate steam store vs steam launcher. You can already add non-Steam games to the steam launcher or launch games without the steam launcher.
The problems identified in the article, and what they are getting sued for, are solely related to the store. So I don’t see how breaking out these supplemental features would solve that.