Good book prints being replaced by their "ADAPTED INTO A HIT TV SERIES/MOVIE!" prints
This SERIOUSLY gets on my nerves as a book collector. I like my books looking good, and almost none of these prints fit the bill of a good-looking print. Especially for book series, where only the adapted book(s) got the new designs, so the spines and covers within the series fail to match one another.
Some good examples of this that I really dislike are certain prints of Project Hail Mary, the Martian, and A Song of Ice and Fire. In the case of the first 2, the new covers are just outright bad compared to the originals. Why on earth would I want to stare at Matt Damon's face instead of a guy in a spacesuit walking on Mars? And why would I want to also stare at Ryan Gosling's face instead of a spacesuited guy drifting through space? It's so much less interesting and so much worse.
And ASoIaF outlines another, possibly even worse situation, where a perfectly fine cover is infected by a random, colorful, impossible to ignore advertising strip. I don't personally care for the covers, but they would be entirely inoffensive if it weren't for the blatant mentioning of the show.