To my understanding it's only in the last 10-15 years that Hirshfeld, Institut für Sexualwissenschaft, WhK etc are being recovered even in Germany.

It is so egregious. At the site of the Opernplatz book burning, which is the nazi book burning etched into our collective memories by the nazi-produced filmreels (they were bragging!), there is now a commemoration: Empty Library created in the 90s:

With a plaque reading

"Das war ein Vorspiel nur, dort wo man Bücher verbrennt, verbrennt man am Ende auch Menschen."

("This was but a prelude; where they burn books, they ultimately burn people").

Nothing here to suggest that the specific target was chosen due to contributions to the liberation of LGBTQ++ people, that it was primarily motivated by hatred of gay, trans, and gender non-conforming people. Literally just participating in the erasure set in motion that day.

(Also I really have to say that the tragedy of this event isn't that they burned books as in published works which exist elsewhere. but that they burned thousands of documents which were totally unique. The Institute contained the world's largest collection of LGBTQ++ culture and in-depth first person accounts of LGBTQ++ life around the world from all walks of life. It's just my little hobby horse but I think it oughtta be considered a destruction of primary documents, not a book burning. We lost not a library, but an archive.)

Sorry for being so vigorous in my agreement... I concur the split is worth looking at and understanding because it became a sort of template for a pattern that would keep happening over and over again in LGBTQ++ communities, each generation having to go through it anew. The ones who embrace gender variation vs the ones who eventually become fascists. (Also they had another split on the subject of criminalizing sex workers which sadly Hirschfeld was on the wrong side of due to his class affiliations, but he lost and the org as a whole made the right decision. But then unfortunately the nazis took power so everyone lost.)