The US motto is: "Buy junk you don't want, with money you don't have, to impress people you don't like." If you're rich you'll get richer in the US, if you're poor (relative to Western Europe) you'll get poorer in the US. Most of the taxes you'll pay will be spent to bomb civilians, fund terrorist and dictators, starve brown people, spy on you, eradicate the environment, subsidize multi-billion dollar banks/corporations, and grant money (w. no interest) to some of the wealthiest people in human history for existing.
Infrastructure is at best degraded, and worst poses a severe threat to human health. Inner cities are crime-ridden cess-pools of drugs, human trafficking, legalized extortion, intergenerational poverty, and institutional corruption.
Jobs here are shit unless you want to work in the military or its' very close associated corporations, in which case good luck getting in. Worker protections and rights have/is/will continue to degrade because the US effectively outlaws unions, organizing, or protest. There is no labour party, and the small ray of hope in the political sphere doesn't have a snowball's chance in hell of getting elected, let alone actually fix any deep-rooted systemic issues.
The US is a police-state, it has the high incarceration-rate in the world. Since you're European it may not be as bad as others but no-one is safe. 97-98% of those incarcerated don't have a trial, and the prosecution will use evidence gathered via illegal means (NSA surveilance and/or illegally obtained documents you may or may not get to view). None of this mentions things such as bail, heavy fines for minor offenses, and the fact that the police department and "criminal justice" system actively and knowingly push people into commiting crimes in order to gain or maintain their bloated budgets and the prison, bail bond, security, etc. racketeering scheme.
Americans on average are obese, asocial to their community, anti-social in world-view, lonely, aggressive, rude, petty, uneducated (even the ones that went to college 4+ years), disconnected from the rest of the world, sensitive, depressed, anxious, and totally entrenched in addictive behaviors. Not to mention are probably the most propagandized population in the world, 7% of americans have a visas to a foreign country, not including for military purposes.
The military is worshipped and there is an ingrained sense of hyper-nationalism, every corner has surveilance cameras and a US flag.
As far as QoL goes, if you're not rich don't: Get sick, get injured in an accident, divorced/married, opinionated or passionate about anything (except for fashionable consumption), attached to anyone outside family, pregnant, conned, arrested, or hopeful for your future. This'll save you a lot anguish there. If any of the above does occur, you've got the login already...
Caveat: I'm generalizing, but it's universally true no matter which region you're in. Some places are worse than others, some ethnicities are treated better than others. All in all the state you're in doesn't matter, in some you can marry minors and cousins, others tax you into poverty, Most are desolate wastelands with scarce populations and resources.
Tl;Dr: we're at a race to the bottom, and going nowhere real fast.