Try re-reading the original post. I said "rank your experience with the iPhones you've owned." Of course each year's iPhone is "the best iPhone ever made". And of course newer phones are better than older phones. I'm happy with the progress made over the years and not one of the cynical people claiming that there's been no innovation with the iPhone. That's not the point.Sorry but this OP makes no sense to me. I started with the v1 iPhone and liked each new iPhone I purchased better than the previous one or I would not have bought it. And my protocol is to hold on to the old iPhone for a few weeks just to make sure.
IMO every year the iPhones have improved. On years when I did not upgrade I still spent substantial time testing friends' iPhones, because back then cell service was particularly problematic and if a phone improved connectivity it was a big deal. The 4s was the quantum jump for me as the first year that I found the iPhone camera good enough to be really useful.
The point is that, at the time we own each phone, our experience using them varies and can be compared as better or worse. For example, I enjoyed owning the 4S more than I did the XS, but that doesn't mean the 4S is better than the XS (it has a worse camera, smaller screen, etc) or I would go back to using the 4S. It means that, at the time, my experience of owning the 4S was better than my experience of owning the XS.
I think the meaning is rather obvious and most other commenters seem to get it.