You joke that there's no potatoes one time, and your players will never forget.

The biggest thing that irritates me from this is the implication that anybody is arguing for "historical accuracy" to medieval Europe in a setting that has dragons and goblins that shoot lightning from their fingertips. If, for whatever weird reason, the DM doesn't want potatoes to exist that's okay, but you're not waiting for the Columbian exchange to bring them over from the Americas because the Americas don't exist here. If you have a player character that's a shape shifting sentient blob who casts illusions and is on a quest to seduce every milliner they can find then a plain tasting sausage made from fine ground questionable cuts of meat shouldn't be seen as a stretch.
Additionally, as someone who majored in History in college, I can assure you that most people insisting on "historical accuracy" on any one or two things they learned from a tweet or a tiktok about are almost definitely getting fifteen other things wrong in any given session.
- I think one could argue that fantasy isn't based on the reality of the medieval ages, but on the collective beliefs and myths of that era.
  As a side effect, though, the countryside would probably be filled with giant snails that you'd have to fight.
  
  I'm putting giant snails into my homebrew world now. It's a skypunk setting so I just have to decide if the snails are native to a specific cloud enshrouded plateau, a flying nuisance species of blimp-mollusks, or an invasive species that shows up everywhere. Maybe all of the above.
  
  ...which sounds awesome...
  
  It's based on Lord of the Rings.
- People want to feel like they're in a historic setting, but they also want dragons and potatoes. 🤷‍♂️
  
  Dragons were probably based on dinosaur bones, so the potatoes are somehow the less accurate of the two

My take:
It's not even set on Earth in the first place, so "historical accuracy" is a non-starter. This world can be whatever you want it to be.
- In my world, running was recently invented by Thomas Running in 748 when he tried to walk twice at the same time.
  
  I believe it was Running who stated "If I have seen further, it is only because I have stood on the shoulders of giants." Referring, of course, to the works of noted giant Thrynn Walk.

One time another player and who both speak spanish were playing tieflings and decided that tieflings are native to mexico so we'd make jokes about our native foods that no one knows about bc they are "from mexico". Anytime we spoke infernal in game we'd just speak spanish irl bc the other players couldn't understand it. Super silly
- lol

Why wouldn't your setting have potatoes? Does your setting have Peru in it? No, no Peru? Gee, then it sure sounds to me like you get to decide where potatoes come from in your setting; they don't have to be a "new world" food if you world doesn't have or has a different "new world."
- Potatoes come from the Elemental Plane of Earth.
  The mighty DM has spoken!
  
  Pomme de Terra
- I'm saving that for a "journey to the new world" campaign at some point in the future.

Potatoes? What are potatoes?
- You know - boil 'em, mash 'em, stick 'em in a stew.
- Sounds exotic.

I still get teased about a player claiming bears can't go backwards and I just incorporated it into the battle. It was a one-shot for new players (and new GM). It was fun. Another player got pissed on to put out a fire. Fun times. "Anything goes" can be fun, don't overthink it sometimes

You think that bad, wait till you hear about wizards selling spells to America to get guns.

Meanwhile, Bob's Bison Burgers has been trading in Pavis since the early 1980s.

Can you explain how potatoes led to hotdigs?
- At one point when people on Twitter were arguing about the historical accuracy of LGBT+ groups in a DnD setting, I made the argument that anyone who includes potatoes in their setting doesn't care about historical accuracy anyway. This led to a discussion about what would be missing from a medieval setting and the conclusion that a "historically accurate" DnD setting would have gay people, but not potatoes. This became a running joke.
  Fast forward a few months, and during a fair there's a vendor selling "sausages in a bun, topped with mustard sauce or sauerkraut." The players caught on to them being hotdogs, and it sparked another discussion about what foods were available in a "historically accurate" setting.
  (Which, all those ingredients would have been available to the setting, even of they weren't eaten in that configuration.)
  
  Sausage (at least forcemeat in casing) dates to Mesopotamia, 3000BCE.
  I don't think the innovative leap to put that sausage in between bread is a world-breaking defiling of historical accuracy, personally.
  
  If I were a player, I would have asked if it's a sandwich. Just to watch the world burn.
  
  And on that argument: being queer is normal. Queer happens. Bigotry is what's specific to a culture.
  
  At one point when people on Twitter were arguing about the historical accuracy of LGBT+ groups in a DnD setting
  Why wasn't your first response to gesture broadly towards ancient Greece? Homosexual relationships were fairly normal and marriage was mainly for having children.
  In a strictly medieval Europe setting there's documented examples of homosexual relationships, but they weren't normal due to suppression by the catholic church