That's a very big generalization, assuming that we know how TCMA is taught in every school of every conceivable system/style, in every country. That's a rather broad umbrella.
There have been schools/practitioners (definitely since, and almost certainly before, the boxer rebellion) that emphasized the performance/artistic aspect and deemphasized the combative aspect, just as there have always been other schools that emphasized a combative approach. And many emphasize a balance of the two. This phenomenon isn't just a recent occurrence.