I don't care if someone used AI for a free cover, but I think it's highly hypocritical of writers to use AI covers, and then turn around and whine about people using AI to write. (Yes, including whining about people who use AI to write an entire story then post it online.) It's unfair to artists and designers, who also have to deal with the struggles of competing with AI. They are getting thrown under the bus there.
Also, I am far more likely to click on a book with a poorly designed cover than something obviously make with AI. All that aside, I don't expect anyone to shell out money for something they're doing for free. Basically, I frown upon using AI but I also understand why writers are using it for covers, and might still read a story with an AI cover if everything else about it is good. It's more of a minor gripe.
Honestly, I wish writing websites were more like ao3 where stories don't have covers at all. It'll put all of us at an even playing field.