I’m at a weird middle ground where I’ve never bought a proxy card before and never will, but I’ve also made proxies of cards I know I’ll never own (ex. Scramble Eevee, Playtest Eevee) as well as custom cards featuring my original art which I keep in a binder.
I think that proxies and customs can be a lot of fun to make or collect as someone who’s into art/crafts. But the moment they’re bought/sold, you run into the problem of potentially profiting from someone else’s art. Whether this is official TCG art, stolen fan art, AI art, etc., I think this is where proxies can get unethical and my opinion on them starts to shift.