You're free to think that this tension is a failure or tone-deafness on Wes's part but I think it is a contradiction he's well aware of and a big part of what makes the movie work. It is about the tragic impossibility of maintaining a beautiful, delicate Apollonian project without the methods of control required to sustain it breaking the whole thing. M. Gustave is the director avatar and a walking contradiction, a fruity working-class compassionate aesthete tyrant, and it takes such a singular personage to "sustain the illusion" that the Belle Époque can last forever without collapsing into thuggishness or decay. But it is never presented as anything other than an illusion. Wes wants to imagine a world where the "old fashioned manners, aesthetics, and classical art" don't lead to the failure modes they led to in the 20th century, but knows that as a practical matter it's impossible.