A way to update preview styles of WYSIWYG editor?

Is there anyway to simply update the styles without extending the entire WYSIWYG editor and updating PreviewWYSIWYG? It seems that in V3 there was potential to update singular components, but in V4 it looks like that functionality was removed in lieu of the extension/plugin/bootstrap system. Unfortunately, I don’t want to change anything about the functionality of the editor itself instead just how the preview styles present. Copying the entire default WYSIWYG editor isn’t really great for maintainability.