I agree generally but of course “Folksmusik” should never be used at all in German, even if someone prefers translated genres, because this word doesn’t exist in German 
It might be “Volksmusik” and that, I agree, is something completely different than Folk.
I am wondering, though, how you get German genres. Is your Roon running with German user interface? And if you go to the album editor and scroll down to the genres, what is your setting for Localized Genre Names (which has been a new switch since the localizations have been introduced)
I guess this was the related announcement:
(My bold emphasis)
I am running Roon in English, though, although my native is German, and so I am not seeing how it behaves with a German user interface. As Mike wrote in the announcement,
others remaining in English based on feedback from users like you!
So I hope they take the Folk vs Volksmusik conundrum into account.
This exists in the other direction as well. In English, I have genres like Swiss Folk (in International > Western European Traditions, which is also a bit strange (is it Folk or Volksmusik? I don’t have any albums in that one, so I don’t know)
“Folk”-alike genres are a bit over the place anyway and it’s difficult to make sense of it, but I’ll leave it here for consideration There are many others, of course, that I haven’t listed.
However, there is a separate “Volksmusik” even in English, so no need to conflate it incorrectly with Folk
Some examples to illustrate that it’s generally difficult as far as I can tell
Folk
International > European Folk
International > Central European Traditions > Volksmusik (which would normally be a specific German/Austrian/Swiss genre, in part Northern Italian and Slovenian, which is not exactly the same as the English Folk in the sense of Dylan but somewhat similar in a sense to “Asian Folk” or something like that, as being a specific local folk tradition)
International > Central European Traditions > Hungarian Folk (makes sense I guess)
International > Folklore (not quite sure what this means / how it differs from Volksmusik as above or various international Folk as below)
International > International Folk
International > Traditional Europan Folk
International > Western European Traditions > Italian Folk (but Italian Music is on the same level in Western European Traditions, while Mediterranean Traditions is directly in International)
International > Western European Traditions > French Folk (but French again is on the same level)
International > Western European Traditions > Spanish Folk
International > Western European Traditions > Swiss Folk (difficult where to put Switzerland, Central European like Germany and Austria or Western European like France or Italy. Nothing’s quite right)