The fact remains that you lose an employee for up to 12 months, and you have to take them back into their previous position afterwards.
Compounding the problem for the employer, is the fact that fathers are also entitled to the same amount of time. Both parents can share 14 months Elternzeit, so both parents cannot take 12 months off each, but they can take 7 months each either together or consecutively.
So the father could technically take 12 months off. Therefore, avoiding hiring women is not a valid strategy (and it shouldn't be either).
If you want to avoid these situations, then just hire contractors, but that will cost you more. If not, just stay in the USA. Europe doesn't need employers that treat employees as slaves. Employment in Germany is more like a long term two way relation, and regulations are made with that assumption in place.
In Germany it seems easy enough to get to 5-10 people with essentially founders and contractors, or expats, or corp to corp. I wonder if something like a PEO could exist which has the long-term employment relationship with the employees, who can move between startups -- it wouldn't be a "staffing agency" or body shop which just provides a bunch of morons for a low price as needed, but a way for employees to be essentially consultants and either promote themselves to companies, or be recruited by companies, without friction.