Yeah, this really isn't new
I remember when I was growing up in a mostly white suburb, any perceived outsider was watched by neighbors. Some neighbors more than others - depends on the levels of racism. Perceived outsiders were discussed and suspected. Doubly so if they were not white, because they were more easily picked out due to skin color. "What are they doing here?" People were all protective of their perceived territory.
In the age of smart phones and doorbell cameras, more and more people are becoming the neighborhood hall monitor. Next Door is not helping this at all. Post after post, "What's this car doing here?!" "Does anyone know who this delivery person is?!" "I filmed this person walking down the street at 1:53pm along Maple Lane."
I live in a more diverse area now, but it's a constant stream of paranoid shut-ins. People say Trump, but this has been a thing for awhile, and it happens plenty in blue areas. I think social media and the fact neighbors tend to be more isolated now has aggravated it, but also made us more aware of it. My neighborhood seems friendly enough, but I could not tell you the names of more than three people on my street.
There was an incident not too long ago. A post about a man who walked out of a path in the woods. Which tons of people walk down for leisure. "This man emerged from the woods this morning and started walking down XX Street." This woman followed and filmed him from behind. So we all got this riveting footage of what seemed to be a middle-aged white guy with a balding head in a post filled with paranoid thoughts and fantasies about all the no-good the man might be up to.
Go back in your house, Karen. If they're not on my property, I do not care.