[Kleb]

The 3 month period is arguably pro-labor.

In the US, you can be fired and can similarly fire your employer at the drop of a hat.

French employees are protected from layoffs and employers are similarly protected from ghosting by problematic employees.

While the notice period is 3 months, employees and employers can often end the relationship in less time depending on the context. Essential employees usually don't get to leave early. There are a lot of caveats to this, so don't take it as a categorical truth.