I find lot of seafood disgusting, and the unsustainability of wild caught seafood is just the cherry on top.
Unagi. Doesn't taste that special and has a texture like dried out overcooked fish complete with the occasional sharp scale or bone that stabs your throat. Definitely not worth decimating wild eel populations for.
Related, any kind of fish eggs. Whether caviar or salmon roe sushi. They're like those popping bubbles in bubble tea but instead of a nice sweet fruit syrup it's concentrated fish stink that coats your tongue and overpowers everything else.
Oysters and clams (bivalves in general). You're literally eating its entire digestive system complete with poop. The crunchy sand is just a reminder of that. And eating it raw is a great way to get parasites and hepatitis.
One that's not seafood: asparagus. People say it makes your pee stink but somehow don't talk about how much the vegetable itself stinks going in. Maybe I've just never found a cooking method I like but I've never tasted an asparagus that doesn't make me wince when swallowing. I personally love the vast majority of vegetables, many of which I prefer compared to meat, but asparagus (and Chinese bitter melon) are exceptions.
Any kind of alcohol in general. I think beer tastes and smells like the liquid at the bottom of a dumpster, so does wine, and any kind of spirit tastes like literal poison. Whatever psychoactive effects it has is not worth the constant nausea during and after drinking. If I'm looking for psychoactive effects, I prefer edible cannabis extract, still doesn't taste that great but you only need a tiny amount to get high which you can chase down with regular food to make the taste go away.