Well..... it's going to be hard to claim he's a lazy dev, at least....I think what was missing back then was mostly art. And he probably added new ideas as time passed.
Main issue I see is that he seems to do the work twice, which is insane.
Once in the "full game" behind closed door, then he cuts off the full game and releases a demo, full of bugs probably because of the fact it was cut off.
No wonder it's slow as hell.
As for release date, honestly I think it doesn't matter anymore what he announces. The proof is in the pudding, aka when he actually releases it.