Kanye was a different kind of act to begin with tho. He was rapping about being a college drop out and recovering from his car accident over classic R&B samples during a time when hip hop was overrun with ratchet southern party music and the standard former drug dealer/gang affiliated cliches -- he wasn't "hard" to begin with and was always kind of different so it really wasn't a stretch for him to go outside of the hip hop box with 808s. He didn't have any kind of street credibility to lose when he was never "street" in the first place. .
Anyway, to answer the question I think it really varies depending on the artist and how they built their following. Certain genres are more fluid than others; like, R&B artists can do pop and go back more easily than hip hop acts can, but, then again, the execution is everything, too. Jay got clowned like hell for doing Sunshine, but, then he later figured how to better fuse genres and appeal to the mainstream while still feeling "street" with Hard Knock Life and that ended up being huge.
And then you take somebody like Ja Rule who came out super hard with Holla Holla and then he started harmonizing with R&B singers on his hooks on the next album and 50 Cent came in and literally destroyed his entire career mocking him for "going soft" with Wanksta, so
it really just depends.
Bow down, flop pop stars.