I don't think it's comparable to the Steam Deck, in the sense that the Steam Deck has always been about playing existing games and the PlayDate has always been

I don't think it's comparable to the Steam Deck, in the sense that the Steam Deck has always been about playing existing games and the PlayDate has always been about completely new games for that hardware. They serve different use cases. I don't have anything to say about the Analogue Pocket; your comment is the first I heard of it.