Tsk. "You" should have been capitalised, rather than "Agree". It's not "Do you AGREE", it's "Do YOU agree?"
Anyway, he's right. Going back to the 4th gen, of course, all games were in 2D. Quite a few PS1 games, too. Nowadays, it's less common, and mostly reserved for downloadable games: BC Rearmed, Trine, Mega Man 9, etc.
There have been a few on disc, like NSMBWii and LBP, and they're both great, so I suppose it can still work, if it's made well. They are both 3D sprites on 2D planes, though.