It has sort of been said already, but I didn't find a reply stating my exact criticism so I'll chime in. Lemmy and the fediverse is confusing. Instances, federation, de-federating, and all the other techno-garble is not something most internet users have any frame of reference for and I imagine it is very off-putting to a vast majority of potential users.
I'm not usually one to harp on user experience but it's just a mess trying to get into this whole thing. I was driven by a hatred for reddit to figure it out and I'm a software developer by trade, but still was scratching my head at wtf all these terms were and how it all works. Lemmy and the fediverse desperately needs some onboarding/marketing work and to ditch this sentiment of "if you can't figure it out then we don't want you here."
I think he has a point that fixing the US is somewhat hopeless. There are many pieces that go into the puzzle that is the United States and its citizens and together they create such a hostile and undesirable place that is adamantly resistent to change. Not only were our cities literally demolished to make way for the car, the whole idea of driving and what that means is deeply engrained in our culture and identity.
This isn't just about removing stroads and designing some cutesy livable spaces and parks in cities. This is about changing the identity of what it means to be an American. Do you think you could convince even a portion of Americans that the European old way of living is better than the American way?