I had the opportunity to move there and have spent a lot of my life between both the US and UK, since childhood.
I wouldn't move there now despite it having been a something I was working towards for most of my life. My own reasons.
Guns. I've been there at points of tension and every trip to the supermarket/mall/busy place felt like a potential mass shooting event. I was in Orlando when people were murdered in a gay club, because they were gay or allies. The church I attended had armed security guards at the door. A friend of a friend was shot dead at point blank range coming out of a local bar because he was Muslim. I was in a mall with my extended family, with us all scattered in different shops/food court when someone let off loud poppers/chinese fire crackers as a joke. It of course sounded like automatic machine gunfire and was the same month as the attack on a Country Music Festival in Las Vegas. Everyone started screaming and running, some of the shops started bringing the shutters down to go into lockdown mode with customers inside, people were getting separated from their kids...it was chaos...people got injured in the stampede...an old person had a heart attack...You just couldn't go about your life in a relaxed way.
I wanted kids. I'd have to send those kids to school everyday wondering if they'd be shot at school. At the very best, they'd have to take part in active shooter drills from 6 years old, which were portrayed as real and left many kids traumatised.
Healthcare...too many known cases of insurance not paying out for cancer/lifethreatening illness, seeing friends being diagnosed with conditions they didn't have by quacks who wanted big payouts, extortionate price of medications for the elderly or chronically ill...seeing young (usually Black or LatinX) victims of shootings/RTA's/sudden life threatening emergencies turned away at ER when they couldn't provide insurance details. The cost of a natural birth was £15k at my local hospital. Any intervention/C-Section/NICU stay could easily run into hundreds of thousands of dollars. Corrupt big Pharma...constant bizarre adverts selling drugs while watching TV.
Fake news. Lack of critical thinking skills amongst a huge proportion of the population and lack of awareness of life outside the USA (or often one's own State, especially in the South/Mid West). So many people honestly thought all of the United Kingdom was exactly like Epcot. Or that we are all getting stabbed by jihadis in the street and that there was Sharia Law in London now. Seriously.
Trump.
Biden.
The Supreme Court.
How easy it is to lose everything...house foreclosures, health insurance attached to jobs, lack of a safety net for those who fall on hard time.
I found the constant displays of Nationalism/Patriotism uncomfortable. America is obsessed with itself and it's Veterans. A day out at a theme park, or a trip to a show might lead to being forced to salute the flag, stand for the flag/national anthem, applaud the veterans who were encouraged to stand. From school, children are forced to pledge allegiance to the flag of the United States.
Food prices are insane. Quality of food is poor. At worse scary with hormones and antibiotics and god knows what pumped into poultry, meat etc. Ultra, ultra, ultra processed foods and hard to escape.
Better holiday pay, maternity leave and employee rights in the UK.
I've been there during multiple natural disasters. Katrina etc. The response is terrifyingly lacking. Apocalyptic scenes on the roads or at airports. Water running out. Shop shelves empty. Genuine fear you and your family might not survive. Never seems to improve even through hurricane/twister/wildfires seasons happen every year.
Not being white and having to deal with cops. I can't even. The fear of seeing your elderly, sick, black dad dragged away by armed cops at the airport for no reason other than him being the only black male on the plane...him being detained for hours, his insulin and vital meds taken from him and begging for his release. Almost every time he flew into the States.
I could go on and on. For a long time I would have said, I'll just enjoy my holidays there but I can't even say that much anymore. Trips to the US aren't fun for me anymore. In the past 10 years it's become somewhere I've felt increasingly on edge and felt relieved to get out of.