I was getting really tired from AI art from main page, and since there is no built-in way to disable it, I've decided to create a script that removes all such art.
I've tested this script only with FireMonkey extension, but it should probably work with other similar extensions like ViolentMonkey or TamperMonkey
[EDIT] Decided to stop being lazy and made a proper version that does not require code editing: https://greasyfork.org/en/scripts/495153-wallhaven-hide-ai-art-from-main-page
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For script to work you have to paste your API key on line 12, i.e. replace '' with 'YOUR_API_KEY'.
Script: https://pastebin.com/Cm80p4Fk