Grilled liver and onions and jarred Gefilte Fish. Both I grew up eating as an Ashkenazi jew with a working mom who didn't have time to make her own Gefilte Fish haha. I do understand that both are an acquired taste though.
Beer. My partner doesn't care for it but I love it. I know tons of people love beer but I totally get the people that don't. It's kinda very different from most drinks!
Sea Oysters! Back when I lived by the coast, I would tag along for a ride with my fishermen uncle; we would cut some oysters with a knife from the side of the port and snack on them through the day; Just opening them up with a knife, add chopped purple onions, avocado, tomatoes, lemon and hot sauce and slurp em' off the shell!
Boiled Peanuts. I love 'em, but they're salty and sodden and messy, and they can range from a disconcerting pop texture to a disconcerting slimy texture, all in the same batch.
Liver and Onion, anchovies, chunchullo, whitebait, blood and tongue sausage... generally these fall in two categories:
Food that has a particularly strong flavor that clashes with what people are used to, and
Food that is made from the parts of an animal that is not "meat" and therefore has an unfamiliar texture.
They're wrong on all accounts - taste is acquired, and people should at least try food out of their comfort zone - but considering that it took 20 years for me to even consider trying shrimp (which still isn't my first choice, but I like it now) I can understand.
皮蛋 a.k.a. "century egg" or, more boringly, "preserved egg".
I get it. I really do. Everything about these from the colour to the texture to the aroma to the flavour is highly alien to most people's tastebuds. (It took me ten years to warm up to them myself!) But now that I pushed through it, they're one of my favourite things.
...edited to add this picture for those who are unfamiliar:
I like Sushi Bake, but when I posted it in one of the food communities on lemmy, I was surprised that a significant % of people in the comments hated it.