Lupe Fiasco is arguable. He himself never sold out, however his label did. His label made a more pop-oriented album in LASERS, but it was against what Lupe wanted and he made that clear.
So would you count this as Lupe selling out or his label?
Gotye definitely, he has always been experimental, and that has not and will not change
DeadMau5 too
Ed Sheeran
Frank Ocean, Tyler the Creator, hell, all of OFWGKTADGAF