Perhaps that was intentional, or came from a collective subconscious desire to commemorate, yet also to forget and move on.

Interwar abstract art such as cubism had twisted and distorted figures, some was a reaction to the twisted and broken bodies of the veterans of WW1. Hitler hated that style of art because he saw it as disparaging veterans, war-glorifier as he was.

It would make sense that a ‘progressive’ regime would want to break with traditionalism and create its own novel style of monument. You see this trend in a lot of postwar aesthetic movements, like the failed housing projects of modernism. They don’t glorify anything; they exist imposingly and have a strong bias to function. Yet this itself is dehumanizing in its own way.

Tl;dr: traditional aesthetics glorify the nation and the state, including its human flaws. Abstract art tends to dehumanize itself as a way to avoid these flaws, especially in the wake of major human catastrophes.

The Soviet and Fascist styles of art which glorified the party and its base straddles both sides.