I think the point here goes beyond just the art world - if you're making decisions that are not in your nature mainly to please others, you'll have to live with the consequences of that, some of which may not be immediately apparent. Unfortunately, we often don't have the means to avoid that, but perhaps we have more than we think.

But to be specific to the film's theme, this rejection of abstract art (often called "formalism", aka. "the study of structure rather than meaning", to quote a good definition from Richard Taruskin) really did have wide support in Soviet society. Not just in publicly-funded art, but also in underground artistic movements (such as "tourist song"). A good description and many visual examples of some of the excellent art that came out of it may be found in the book "Soviet Impressionist Painting" by Vern G. Swanson. It sells for insane prices now, but if you can find it in a library near you, it's well worth checking out!

Funnily enough, at the very same time that this film was made, other animation directors such as Fyodor Hitruk and many others were pushing very bold styles, moving as far away as they could from the realism of the early 1950s. As long as the style remained subordinate to the story or overall point of their films, they seemed to get away with it. Mostly.