I finally traded in my beloved iPhone Mini 13 just under two weeks ago. Of the 4 iPhones I had owned since the iPhone 5, the 256GB 13 Mini was the one I kept the longest, and the overall best iPhone of any of them. But at least for me, it was time to move on. I did like the iPhone Air, and I considered it. But it was too expensive IMO for what it was.
In my case, I bought an unlocked phone outright, and it just didn't make sense to pay $1000 outright for a phone, not counting the trade-in. I ended up buying the iPhone 17e. With the addition of MagSafe and the doubling of base storage to 256GB, it finally became a compelling value, unlike the previous 16e. I am very happy with my purchase. It essentially is a regular iPhone 13 or 14, but with only a single rear camera, but with much newer and faster internals. I almost never used the extra wide angle camera on the Mini, and the loss of that camera was no deal-killer to me. I also don't need ProMotion, and I don't even like Dynamic Island (which IMO is a gimmick). I do wish a smaller phone was still an option, even though I have already gotten used to the larger size of the 17e. And I do love the much-improved battery life.