I guess I don't understand how this particular issue could be more interactive.

I mean, authors could completely do away with main characters and divide all the narrative development equally among an ensemble cast. Which they could and sometimes do, but that would mean the loss of the Chosen One narrative, bildungsromans, coming-of-age stories, etc. And why? No matter what an author does, s/he can't control which characters an individual reader is going to become invested in, so why shouldn't they write what they want?

I feel like I'm missing something here. Like, the real argument is actually about the moral dissonance that arises when an author allows their protagonist too much moral leeway while not affording it to other characters in the same universe?