A lot of them got sucked into the whole “the government is forcing it on you to control the population”, and they simply can’t comprehend that anyone would voluntarily wear what they now consider being the symbol of submission to the government. In their mind it doesn’t work and never worked and you’re just virtue signalling your support of the government. It’s wild and a lost cause.
I’d expect it to get much worse now.
I think a part of it is that english is just the default language and strongly leans american already, so there’s just no demand for a USA instance and people just use the popular or thematic ones for that content. There’s no advantage in laws to prefer US hosting.
The country ones make sense because they’re also a different language, like jlai.lu in french, and the feddits for European languages.