Earlier quoted context omitted.
It's legal because the workers welcomed it. At first. This is one single factory in the entire United States, and it is news because it is so far out of the ordinary. I grew up around a lot of steel mills in the middle of America. What happens is this: Demand increases rapidly but nobody expects it to last. So they go to the union and work out a deal for increased working hours at a higher salary. Everybody, and I re…
The same law has been passed in France where a union's deal can bypass the law (totally crazy idea to be honest). And these deals happen exactly like you described, except that workers are threatened by factory closure. For example it happened for the Smart car factory, they accepted to work more hours for the same pay, with the promise to get investments. Well now the factory is closing and they are pissed off to ha…
It can go up to 60h/week in exceptional situations. Notably, it happened during the pandemic for some essential workers. In the article, that's 84h/week.
For the Smart car factory scandal, the work week was 39 hours, which is more than the official 35, but well within the limit and perfectly legal. The problem is that it should have been paid overtime, but it wasn't, which technically meant it was a wage reduction.
There are still some people in France who do absurd work hours, but not factory workers. Among them are medical interns (that's illegal but still done), self-employed people, and some high level employees who don't work on the clock.