The linked answer from /u/commiespaceinvader is more relevant here than mine.

What is going on here is that the debate between Faschismus vs Nationalsozialismus was one that was laden with political meanings in Cold War Germany. The German left, especially the Communist and non-establishment New Left of the 1960s, continued in the interwar semantic tradition of labeling Nazism as general anti-left and anticommunist political phenomenon. The GDR in particular used the term Faschismus to describe the West, especially the FRG, in its state media. The most famous example of this was the official name given to the Berlin Wall: Antifaschistischer Schutzwall (Anti-Fascist Protection Rampart). GDR media would also use Nazi frequently, but seldom Nationalsozialismus or NS as it was allegedly a slur on the name of socialism.

Roth, as a member of the West German New Left, naturally contends that there was a disadvantage for German historians using the term Faschismus. There was some truth to this; the mandarins of the German university system of the 1950s and 60s were somewhat stuffy and conservative. Likewise, German publishers like the Axel Springer Verlag were very anticommunist in both management and what they published. But this was only part of the story. A number of German scholars and intellectuals hewing towards Faschismus were doing so in an ideologically-freighted fashion. It was not atypical for the German New Left to argue that there was no functional difference between the Third Reich and the FRG. Articles in the magazine konkret, for example, would repeatedly label the FRG establishment as fascist. The generalizing effect of using the Faschismus label smoothed out, or at least, attempted to, some of the very real differences between the politics of the interwar and postwar periods. Using Faschismusduring the Cold War could be construed not as a semantic style, but a political one.

There were German scholars that did use the Faschismus term or looked at the Third Reich within a comparative context and faced little repercussions. Hans-Ulrich Wehler was notable example of a left-orientated German historian who explored fascism and placed the NSDAP within a broader trajectory of European politics of the nineteenth and twentieth centuries, with Germany following a special path that created an especially virulent form of illiberal politics. On the opposite end of the political spectrum, the conservative historian Ernst Nolte made a name for himself with his 1963 Der Faschismus in seiner Epoche. Both of these men became hugely influential figures within the FRG intellectual and academic establishments.

The debates of the Cold War have lessened to a degree post-1989. There is a stylistic preference for Nationalsozialismus (often abbreviated NS in German publications). But this is more of a reflection of the forces of habit and the mounds of scholarship on the Third Reich that show how different it was from its far-right contemporaries. Yet there are still scholars that can describe the dictatorship as faschistische and find an audience.

/u/commiespaceinvader has previously answered Did the Nazi government ever describe their movement as Fascism, or were Fascism and Nazism conflated by later historians? and was the guest on Episode #92 of the Askhistorians Podcast to talk about the history of fascism.

/u/kieslowskifan has previously answered the related question of Why did the Nazis first label themselves as the National Socialist Party if their fascist ideas were the furthest thing from socialism?