(Personal opinion) It is getting anoying with all the germans and their steam keys petitions. Even if you get the game key, it is still region locked as far as I am concerned.
Just extract the zip, create a shortcut to the file named "game" and if you dont like the icon just download a .ico image and set it to the shortcut you just created. If you think that method is too complicated just download the itch.io launcher, the game is literally a few clicks away. I just don't see any benefit from getting a steam key.
That being said, at least they are showing some kind of love to this masterpiece of a game.