fun fact: the german beer brand warsteiner changed their logo with the old long s a few years ago because people outside of germany (and even in germany) would read it as warFteiner :D

https://www.fontblog.de/traditionsbruch-das-neue-warsteiner-logo/

i wrote a paper about this topic in art history class at university a while ago, and if i remember correctly:

there is a official edict from 1941 that says the fraktur must not be used in official documents, street signs, newspapers etc. (all print products) and should be replaced as soon as possible.

it was (probably) still in use after that because they did not have the ressources to replace it everywhere while at war.

the reason for the ban according to the edict is that blackletter is not german but jewish. but the real reason ist most likely that people outside of germany and in german occupied countries could not read any signs, newspapers etc.

the history of the german typography is a really interesting one: https://en.wikipedia.org/wiki/Antiqua%E2%80%93Fraktur_dispute

the nazis actually banned the fraktur later on in favor of the antiqua.

Maybe add some characters like ä ü ö and ß or even the old long s (ſ)?