The US is a big country and there's plenty of places that most people wouldn't like to live (every country has locations like this), but if you're a tech worker, there's no place better in the world to live than in the US. You don't have to live in the Bay Area, you can live in Seattle, New York City, Boston, Los Angeles, or Atlanta. Don't like the city? Okay, there's plenty of affordable suburbs to live in all over the country.
Plus your cost of healthcare will either be free or heavily subsidized, taxes will be lower, you'll be making more money, and the opportunities for career advancement, VC funding (if you want to go the startup route), and opportunities to network will be much greater here.
America is an amazing place to live, whether the internet wants to believe it or not.
The visa scene is US is fickle and very unfriendly even for folks in high tech companies. For instance, the Green Card process is same for a software developer (no matter what company she is in) and a taxi driver. Of course, I don't have anything against taxi drivers, but I do believe education and professional qualifications should play some role in the Green Card process.
Across the entire UK there were only 4 police shootings in to 2016 and only 2 total in all of 2012-2014.
I'm willing to bet America has 4 yesterday (even adjusting for proportion populations)