> Frenchman here. I leave the office at 6pm at the latest, and I take 2 hour lunch breaks everyday. :)

Good for you - not for me.

I do intermittent fasting. I often eat by 4pm.

Should I need the government authorization to eat at my desk at 4pm? (or leave at 4pm to eat at home which is equivalent to you leaving at 6pm after a 2h lunch break)

Or would I need to take a 2h break I don't want to?

Government regulation of lifestyles is acceptable when you have an extremely homogeneous population and culture: this can work in Japan. This might work in France. This sure won't work here in the US.