I feel this so hard. I have difficulty with a lot of historical universes, even without having ever deliberately studied history of anything, just from the trivia I've picked up over the years. But the few historical eras that I've become fannish about - the Regency, the 1920s-30s, and to a lesser extent, the Enlightenment and Victorian era - are the worst, because even when I can keep reading because they obviously tried, I spend the whole time thrown out of the story, which results in bookmarks like "This is really great except that's not how textiles worked in the middle ages and the whole plot falls apart as a result" and "This was fun, but that method of inheritance is just fundamentally incompatible with the economy as written".