Why the hate for the Pearl Diver?
I know it's a somewhat weak card, but it replaces itself in both card and action when played. The only time that it takes up any room in your deck is when you have a terminal card-drawer that can't skip over it. This includes Witch, Ghost Ship, Torturer, Wharf, Smithy, potentially Nobles, and probably some others. It certainly will suck when you draw a Pearl Diver instead of a treasure when you play one of those as your final action, and certainly in such a case I can see ignoring it even if you have $2 to spend as the times it will be useful are relatively minor compared to times it will be dead.
However, its effect is probably a bit stronger than some people realize. I'm of the opinion that a single Pearl Diver improves your draws even when you don't move a card with it. Quantum mechanics-inclined thinkers may look at it as collapsing the probability function of your deck into one that is slightly more advantageous for you. Alternatively, with a single copy and a random deck it is nearly equivalent to "Look at a the top card of your deck. You may move it to bottom of your deck." Once you play it a second time during a shuffle without having moved the bottom card it becomes worse, and with Sea Hag, Ghost Ship, and Courtyard (and I guess Stash in theory) it isn't actually equivalent, but the only reason you'd be loading up on Pearl Divers would be for something like a cheap buy for Goons that helps you find other Goons, helping a Conspirator chain kick off, or loading up your Scrying Pool-based deck with more actions - all of which Pearl Diver fit very nicely in. It also can do more than improve the quality of your future turns: if you have other card-drawing in hand, it will provide some useful information in planning your turn if you have some choices to make. At very least, a single Pearl Diver bought with a 2 copper/3 estate hand may end up providing some help and rarely get in the way. Multiples may provide a lesser effect, but if there's no terminal card drawing there's no drawback at all.
Ok, the card is not great, I understand that. Perhaps it's a newbie-bait card that people end up buying too many of when they should be buying other things, or have them stuck in hand after playing a terminal card-drawer. But those are mistakes that could be made with pretty much any action. Why is Pearl Diver specifically hated on to the extent that it is?