> But what would they actually do if you’d say that you’ve been on call enough already, not going to continue for a week or two?

You have a conversation about it, adult to adult. Why’s that so hard to do?

> sure they wouldn’t terminate you, that’d be too expensive for a skilled employee of which there is rumored to be a great shortage

Yes that’s your leverage in a deal.

> American work culture seems very strange.

Individuals being able to work out what balance of work and compensation works for them by talking to their employer is strange?

The question was how is it legal - it’s legal because the government lets highly paid professionals with leverage manage their life themselves.

It would be expensive to let you go, compared to the costs of fixing it, but if they give in, then everyone else will push back on this, too. Which will be more expensive for them in the long run.

So, the smart thing to do is to make an example out of anyone who pushes back.

Tech workers have no solidarity, so management is very successful at divide and conquer tactics.

While they might not terminate you, they have other means of retaliation - reducing scope of work, assigning "good" projects to other employees, generally making work life miserable, with he goal of driving you out (and making an example of you - better be a good little wage slave - the executive team and major stockholders need to buy another yacht).