Perhaps I'm not explaining myself well.
Sure, one would expect Bethesda to head in this direction at some point, but Doom is the obvious choice for making that push. Doom has 40k+ reviews on Steam and was widely liked. RAGE is also mostly positive in its whopping 7k reviews, but half the positive reviews are like "it was cool, 3.5 stars I guess". With Doom, everyone loved the first one, it was a big surprise to most, people are pumped for the second one, it's a big name with a long history, and the last game was pretty recent so its still on everyone's mind. RAGE at this point is to one degree or another synonymous with disappointment, even if the 2nd one looks like it could be cool: engine wasn't great, buggy on PC, most of the advertised features that weren't "shoot dudes" nobody really liked that much. After all the bad press from Fallout 76, just seems like the last thing you want to do is make a big announcement that your weak-ass launcher that nobody actually wants to have installed is now going to have another exclusive game people aren't exactly clamoring for. It'll hurt sales on an already marginal game and yet still give you bad press because you're forcing an exclusive, which people (especially PC people) always hate. Fallout 76 I imagine got away with it because it's an MMO, so whatever, but for something like this a launcher update and Doom exclusivity would have been a lot smarter. Or Elder Scrolls. People still would have been annoyed because the launcher is, in fact, actually garbage, but at least then you'd have a strong product to take their eyes off that, and you'd be less likely to have to worry about people not buying the game because your launcher sucks.
I guess at least they didn't try to lead with WET 2.