There are federal laws that limit this, typically applied to larger employers making entire business lines redundant (closing a factory, etc). State laws very, some with zero extra protection, some with a bit more, but AFAIK none with European-style rules.
In professional jobs, it's traditional for an employee to give 2+ weeks notice. Most employees will try to stay long enough for a reasonable transition - depending on position/project status, that could be 2 weeks or a month or two.
It's traditional for employers to give 2+ weeks severance. Most white-collar employers have periods that start at 2 weeks and grow with tenure. Including benefits is hit or miss, and a HUGE issue because health insurance/care in the US is so expensive.
I think what you are thinking about is the court almost certainly won't order you to go back to work after you quit.
Just like they have also ruled that mandatory Jury duty is not in violation of the 13th amendment either. Funny how the system protects and perpetuates itself.
But with respect to your point, I am nearly 100% sure that it is not the case that employers can use financial penalties to enforce such a contract. Anything you are paid as wages is pretty much untouchable after it is paid out, unless it was paid in mistake or you intentionally damaged the company or something. The best the company can do is withhold potential future earnings or bonuses, or take back conditional non-wage payments like bonuses within a certain window of time.
This is part of why golden parachutes exist. Your contract has very generous severance clauses which award you lots of money if you follow a certain procedures for leaving, which involves advance notice and such. Fail to follow that and your paycheck just stops the day you walk off. So there are incentives, but they can't go after your already earned wages, paid or still due to you.
That's pretty much what I meant although, as noted in another comment, I assume there are cases where they would try to claw back relocation or signing bonuses. Also, of course, things like RSU vesting.
>they can't go after your already earned wages, paid or still due to you.
Certainly, and depending on how paid time off accrues, anything earned there--which is one of the drivers with "unlimited" PTO because that's not owed when you leave.