It literally is not a ban since it is allowed, and for less than the full compensation the employee would receive by working.
I am not discussing the efficacy as I haven't seen any numbers on how many non-competes are in effect in Germany. I am discussing the ethics of it
But for your argument to be complete I think you need at least some example of someone doing something unethical or wrong because of the policy. The policy exists today so hypothetical arguments fall a bit flat.
To illistrate my point, consider that it is legal (as far as I can tell -- not a lawyer) to walk around in California with a sword as long as it's neither concealed nor being brandished. But it doesn't make sense to argue that the lack of a law against carrying a sword is unethical because of what people might do. Theoretically people might do horrible things while carrying a sword; but empirically they do not, because few people even have swords, fewer still walk around with them, and approximately zero deaths result from it.
It is not a hypothetical situation, unless you are trying to claim that no company anywhere is using a non compete, in which case I just need to pull up the associated paperwork for pretty much every offer letter I've gotten. Alternatively I can go and poll just my social circle and compile the list of non competes.
Anything less than the full salary is unethical to me, and I'm partial to arguments that it should be more as the employee under the non compete is losing out on career growth and raises
They are also making that money while doing nothing.
When poliicians pass laws though, there are often unintended consequences. Good politicians will intentionally create loopholes out of humility, realizing that they don't understand the entire issue and how it will affect everyone.
If the loopholes are too big, then thr policy will be ineffective and they will either need to tighten the loophole later, or scrap the whole policy as unworkable.
Do you think the ban is ineffective? Are there hordes of unhappy German citizens drawing 60% of their salary because they are unable to find better work without violating the non-compete? And tons of greedy companies making zillions of euros by paying people to not work?