Either they ran out of ideas, ou they want profit. Most artists toi hear on the radio these days are all the same:
-Generic lyrical themes (party, love, sex, fun, etc...) -Autotune -Uses different noises to fill the emptyness (unh, oh, huh, yeah, mmh) -No originality -Praised par millions of young kids/teens that don't have a single clue what actual talent sounds like -Alot of them lip-sync at concerts
At the end of the day, they could care less about quality and legitimacy. As long as they're making profit and being praised, because that's all they care about.