I’m curious to know more about that boom and how/when it busted. I suspect it’s just a case of declining sales and rising costs, but details would be interesting. As a kid, I got these mostly as remaindered hardbacks from local mall bookstores, which maybe says a lot. A few remain in print and available: Brian Froud’s various fairy books, especially. But this is a genre of popular publishing that probably fell prey to all kinds of rising costs… Though who knows, maybe boutique editions and crowdfunding could bring them back…