Technically these are all still Latin leters, just that they're written in a weird way that evolved from middle-aged Gothic handwriting as opposed to Latin directly which was the case with English cursive. This style of writing, along with the print-oriented 𝔣𝔯𝔞𝔨𝔱𝔲𝔯, was abandoned for the Latin equivalent by the Nazis for logistical reasons in 1941.
https://en.m.wikipedia.org/wiki/Kurrent https://en.m.wikipedia.org/wiki/Antiqua%E2%80%93Fraktur_dispute
To be fair, i don't think I'd consider sütterlin to be traditional only roughly 20 years after its creation. To day it is of course, but back then?
You're not entirely wrong but Sütterlin was a subtype of German cursive which is much older and they abandoned the (also much older) Fraktur font as well.