I don’t think I have one. I have read and liked a number of books that I would describe as dumb fun / shallow entertainment, including Japanese light novels (like Bofuri : I don’t want to get hurt, so I will max my Defense, Reign of the Seven Spellblades, or Death Daughter and the Ebony Blade, to mention some light novel series I read recently), but I think it takes actual talent to write that kind of books in a way that is actually fun and entertaining instead of just dumb and shallow.

Also, none of these series were particularly trashy (no harem of scantily clad bunny girls, sorry), just fun and entertaining, so I do not really have anything to feel guilty about reading them. While I may have read a lot of classics and history books when I was younger, I now mostly read for fun, and there is nothing wrong with that either.