Isn’t it a bit arbitrary to just divide time into generations like this? It makes more sense for big events in history, like the world wars, but now, I don’t know. According to this I am a millennial, but what does that mean really? That I saw the internet become what it is now? Not a very defining thing for a whole generation imho.
Their “dominance” is the choice of the distributions. Gnome is opinionated, and I respect that they follow their vision. To me this is free software working as intended, people are free to fork Gnome if they want something that the devs don’t want. And apparently, many distributions think Gnome should be the default. Maybe it shouldn’t, but that’s up to the distros to decide.