> I don't think Copernicus did any explaining why at all.

He did. I mean even ask yourself, why would he do what he did if he was just concerned with motion? Ptolemy's model was accurate for predicting motion. If it was just about motion, then the viewer's position doesn't matter.

But Copernicus's enables us to say more. It is more elegant (it was not simpler though). Copernicus was seeking realism. He was the person annoyed with how complex a system was while everyone around him was saying "who cares, it works".

  > That's what I mean by it being a matter of taste, not of truth.

There is no taste to truth, only taste in how you convey truth