The font is Blackletter, which was widely used in Europe, but specifically Germany kept using it until 1941, when Nazis abolished its use. But since Germans used the font, and nazis were German, people think that the font is bad, and should not be used. Similarly, since nazis tended to be clean-shaven and not grow beards, it is well-known that every right-thinking man today must grow a beard to avoid signalling their nazi sympathies.
Interesting factoids about military facial hair to go with your joke:
Moustaches were mandatory in the British army (and shaving them off a punishable offence) for about sixty years, up until the middle of the First World War, where the rule fell out of favour in no small part because too many of the new recruits were too young for anything more than peach fuzz.
The Victorian trend for really big bushy beards emerged in part out of mass public admiration for British soldiers returning from the Crimean War, who had grown long beards to help cope with the extreme cold over a very long campaign, after Queen Victoria noted them with some admiration. Though it probably did land at a time where shaving was somewhat out of fashion.
Mmm...yeah so someone who learned German as a second language and knew a lot about the culture and history explained the toothbrush mustache, as worn by Adolf Hitler.
"So it was because German elite airmen needed oxygen at the altitude at which they flew, within the airplane. I suppose because the cabin was not pressurized. They had to be able to get a good tight fit on the masks, so the only facial hair they could have was a toothbrush mustache, because that didn't make the mask leak.
So in solidarity with elite airmen, to show they were just as masculine despite having so little facial hair, Hitler wore that mustache always."
Which doesn't even make sense, given it was abolished by Nazi Germany "when Hitler's distaste for the supposedly "Jewish-influenced" script saw it officially discontinued"
Just to be clear, people being stupid about fonts is real, but my analogy about beards is meant to be an obvious joke to highlight the stupidity of such reasonings. I am not currently aware about anyone associating clean-shavenness with nazis, although it might only be a matter of time.