Even $50 off the price would make this GPU a clear winner and basically blow out everything up to the $600 price point. AMD just hates winning I guess.
The 7800xt is fairly smaller than the 6800xt. The 7800xt is a 60CU gpu(ontop of being on a smaller fab), while the 6800xt is a 72CU gpu. (346mm^2 vs 520mm^2 )
Its part of the reason why AMD wanted to sit on stock, as they want the 6800xt on the market to deplete before the 7800xt rolled in.