And the weight. A recreational glider weighs about 600kg. They want to build one that carries 3 and later 10 tons.
If a recreational glider crashes into a house, it usually does not cause a lot of damage except to the pilot, see here:
https://www.tz.de/welt/niedersachsen-segelflugzeug-stuerzt-wohnhaus-zr-2446316.html
Now make that thing 20times heavier. There is a reason drones are regulated by weight class.
What is a CD player plug?