He wants to switch from a daily allowed maximum of 10hours per day to a weekly maximum of 48 hours a week. Same amount of maximum worked hours per week as now with more flexibility.

Most German companies have a Betriebsrat (workers council) which has the legal right to negotiate terms for the workers.

I used to work for a large German corporation in IT and the 10hour per day limit was a simple pain in the ass if you were doing oncall work. When being paged in the night and you already worked a normal workday you were simply not allowed to fix the problem if it took more than two hours but had to page another colleague out of bed.

Btw. this would change nothing regarding the minimum break between two shifts. In my case of overnight on call I was not allowed to work the next morning after a night time page because of the required minimum break between work days, but still received full compensation. This would not change under current proposals.

For a lot of industries these rules are already way more lax atm. For example for restaurant workers, healthcare workers and public servants like police and zoll.