It is also a construction thing. Air ducting is very rare in German homes. AC is also rare because frowned upon. And heating is usually provided by warm-water radiators or in-floor loops. But those radiators and in-floor loops are usually unsuited for cooling.

What's more, most heating techs only know about water heating and are unable to solder a refrigerant pipe. So it is hard to find someone to install a split AC or split heatpump, and your average heating tech won't even mention anything about cooling because he can't install it and your existing setup might have to be redone anyways.