And I've yet to see any evidence for this. Unless of course we count all the garbage costing €2 on Steam among the "non-exclusive" but that would be disingenuous. If we only count games that are released on consoles then I don't see how you can justify that statement. Unless you're simply saying that the best games are Nintendo games. They are disproportionately represented in all these lists, that's for sure (https://en.wikipedia.org/wiki/List_of_best-selling_video_games).I totally disagree with just about everything you've said there but.. each to their own.
Again, I am not arguing that there are more quality non exclusives than exclusives. I am arguing that there is a disproportionate amount of quality exclusives to non exclusives.