Doxing and drama are probably the only reasons an artist would go all delete everything and disappear. Or because they got a real art job and doesn't want their boss to find out about their fetish art. Sure, you can delete the art you don't like, but in that case it'd just be the less than recent art.
I don't like my old drawings either, but I have chosen not to look at them.
@ChildOfTheNight Yea, that one hurts quite a bit for me. Their "Student of the Night" blog was one of the earliest things I followed when I got into MLP, but it sadly died right as the action began to take off (it seems).