I think Ariel Pink is pretty sincere. He's trying to recreate something he loves and his music is nostalgic to the bone. He's said that he's trying to use cassette as a instrument just as much as a medium; its a reaction to the fact that just about anyone can make a pristine album these days and also a way of creating a special type of texture and atmosphere.
I can understand not liking it, but to say he is less sincere than, say, Pavement or Sebadoh, I think, is misguided. He justs dresses his music in different clothing than those guys do. Listen to "Immune to Emotion"; lyrically, it sounRAB like it could have been written by Lou Barlow.