Fascists were surprisingly "progressive" in the original meaning of the word. Hitler himself was quoted saying that form follows function and if you look at the plans for their new capital, I would not call it particularly ornamented. I guess "imposing" would be a better description. It's a similar story with the more detailed blackletter fonts - "Your alleged Gothic internalization does not fit well in this age of steel and iron, glass and concrete"
It is a big mistake to conflate traditionalism/conservatism with fascism/nazism, these movements were inherently modern, even when the majority of people under them were not (as is the case in most of the world - the politically active minority creates revolutionary ideologies which are then stripped down to only the essentials by the pragmatic masses).
Nazis and fascists were progressive in so far as they copied Bolsheviks (state control of the key sectors of economy and social programs). In fact they initially marketed themselves to the working class as socialists with nationalist and traditional values, as opposed to the cosmopolitan values of the communists.
A lot of things are imposing but are not Nazi or Fascist. However Nazism and Fascism without traditionalism doesn't make sense. Both (especially Nazism) draw heavily on nationalistic mythology. This is not to say that traditionalism implies either Nazism or Fascism. That should be obvious. My point is that Brutalism has nothing to do with either Fascism or Nazism.
It is a big mistake to conflate traditionalism/conservatism with fascism/nazism, these movements were inherently modern, even when the majority of people under them were not (as is the case in most of the world - the politically active minority creates revolutionary ideologies which are then stripped down to only the essentials by the pragmatic masses).