Are they sure that’s the direction of causation? Because eating undercooked bear is the sort of behavior I’d expect from people who were already infected with brain worms.
It's the same thing you get eatting undercooked pork. Only recently did the pork industry manage to get it mostly out of their herds so now the "recommended temp" to cook pork is dropping.
But it's still very common in bears so you have to treat it like pork and cooked it to 165*
which sucks, I'd love to try a juicy rare black bear steak.
Same, that's one of my favourite ways to eat it, basically if it's a big enough whole muscle it gets ham-a-fied, the rest goes into grind for summer sausage and meatballs.