I am trying to imagine. The end result is similar. In Europe it would be "unlimited unpaid vacation days on top of the mandatory paid vacation". The same problems will appear: self-restrict to taking it. Management would never help employees to take the days. My manager does not help me even take the mandatory legal days, it's all on me to deal with priorities and deliverables and find a way to still take vacation. With decent managers, there would be no burnout, but we are in a crisis of morals in corporate management, the job of most current managers is to make a career at the expense of the employees.
Oh I don't doubt that the mandated leave entitlements and severance would be kept. But I think actual leave taken would increase, bounded only by the fact that taking holidays is expensive, and kids have to go to school. So you balance your career progression and hence holiday spending power in the future against immediate satisfaction from taking leave. I think many jobs without a meaningful career trajectory would experience massive leave taking. Remember, these people can't be fired or demoted in any way. If the work has to be done, it might even cause employers to incentivise work differently.
I don't think career plans matter. Workload does. If you have a work plan and taking any free days puts it in jeopardy, you will not take any extra free days. And if not meeting the full work plan results in no salary updates, which is technically not a punishment and it is allowed by law in most of Europe, with some inflation (over 10% in my country) it is practically a pay cut, so you can't afford that.
That would certainly not fly in France, it would land the employer in a tribunal. Paying someone less because you gave them more work than could be completed during working hours?! Non, impossible.
