The OP just decided to strangely translate a clause that asks for employees to not demand work during cation (the usual US "I'm still reading my emails") and that they cannot work at another job in that time.
Re:Workers of the World, Take PTO
by evilspammer on Monday May 01, 2023 @01:05PM
(#35775768)
it's more to prevent employers from making you work during vacation
Literally, it's about preventing taking a second, paid job during vacation from your first employer. So it's not entirely clear whether this is about protecting employers or employees. As far as I know, non-competes for blue collar workers are uncommon (or at least they used to be).
I don't have the immediate texts at hand but I cite sources in my guide about taking time off in Germany. The law is very unambiguous about what vacations are for. A nice example is that if you get sick during your vacation, it counts as sick days and you can use your vacation days at a later time.
https://allaboutberlin.com/guides/vacation-days
My guides about sick leave and sabbaticals just add a bit of context. Sick days are really well protected.
I'm from the US, and this sounds very strange to my ears.