I don't see that happening at all, tbh. They just had a billion dollar hit with Black Panther and also respectable successes with Spider-Man, Doctor Strange, Ant-Man and the Wasp and are currently pushing Captain Marvel. I do think it's inevitable the X-Men are going to be major players, but I seriously cannot see a situation where that means Marvel downplays everything else in favor of them when their entire empire has been built by characters who weren't the X-Men or Spider-Man.
Just given how massively successful the Guardians of the Galaxy movies have been for them, we are likely gonna get a third movie sometime within the next few years, even with all the Gunn controversy.