I waited a little over 4 years to upgrade from the Samsung s7 to the iPhone 13 mini. I could gush over how much I love this phone, both the hardware and software are a delight.
I've owned the original iPod touch as my first foray into smart phones, it was small (~4.3 inches tall) and it was cheap (something like $300 for an iphone without cell service). Upgraded to the nexus 5, even though both had bars on the tops and bottoms of the screen, the extra inch it offered felt magical at the time, not too big, not too small, and the price (used) felt reasonable as 'real' phone. On top of that, stock android felt so much better than iOS at the time. I then 'upgraded' to an s7 and regretted it for 4 years. The phone was similarly sized to the nexus, but it didn't feel any larger to me. Similar to the Nexus, it was a behemoth of a phone that for my tiny hands made it difficult to hold without dropping it. Unlike the nexus, which had an incredible easy snap-off rubberized casing, the s7 had this awful glass casing, which screamed 'put a big bulky case on me!'. I got the seemingly best thing I could find, a big bulky OtterBox for $50, which seemed great, but the rubber blew apart after a year. Between the case never fitting snugly and the sheer bulk of the phone+case, getting it in and out of pockets was a serious ordeal, it also made the wireless charging not work at all for me, this meant that I had to fiddle with the stupid cables constantly. On top of all that, the OS that Samsung shipped with the phone was utter crap. For such an expensive product, I was shocked by how bad it was, and sure you can mess around with roms and such, but who has time for that crap? But hey, at least the battery was massive and I only needed to plug it in once a day.
Que, iPhone 13 mini. The phone has a slightly smaller profile than the s7, but the screen feels (and is!) massive. It's still made of glass, so I had to put a case on it, but apple sells great thin cases (tbd on lifespan) that look good, slide in out of my pockets well, and do not interfere with wireless charging, better yet, the mag-safe cases made it WAY easier to do so. With that said, it's not like I even have to charge it very often, I'm getting multiple days between charges, 3-4 if I put it into battery saver mode. I have 0 worry about ever running out of energy and being unable to charge, something that on all previous phones, compelled me to stash chargers everywhere I went and carry one around. It's a shame about the recent turn wrt to privacy, but aside from that, the software is a magical delight, miles ahead of android in my opinion. Given that I paid essentially the same price for the 13 mini as I did for the s7, and that the trade-up rates are fantastic, I view the price as an absolute steal for the phone. I truly don't see myself going back to android in the future, Apple gave me exactly what I wanted out of a phone and I pray they keep this smaller line of them around.
As to why there are no big Android contenders in the mini-space, I'd guess it's a combination of apples hardware/software being ahead of the curve, and that the perception is that the average android consumer wants a bigger phone. If I'm being a bit more cynical, companies probably also assume they can charge higher prices for bigger devices/batteries. If I were to place a bet, I'd guess that there will be a slight rebound away from phablets in the coming years, Apple proved they can strike an incredible balance between size and battery performance at a price that is reasonable compared to other flagship phones on the market. They've set the trends/pacing in the phone space for years now, I don't have a reason to believe it's going to be any different in the coming decade.