I look at it this way:
I bought an 128GB iPhone SE in 2017 for $499, if I remember correctly. (And if
this Verge article is to be believed.)
That phone lasted me almost four years. I've managed to never break a screen or incur any other damage outside of minor scratches on the screen from daily use. The only real problem is the battery, which barely holds a charge these days. A new battery would cost me $50 from Apple ($25 if I replaced it myself) and I could probably get another year (or more) of use out of it, but I'm just ready for something fresh.
It helps immensely that T-Mobile has a killer trade-in offer, more than I could get selling the phone secondhand myself. They're giving me $215 back on a $749 purchase, which actually almost brings the phone down to the price of the 128GB iPhone SE I paid for in.
And considering the iPhone I purchased in 2017 was a storage/price refresh of a 2016 model which in turn was actually a smaller variant of a 2015 iPhone, I was buying "old" hardware from day one. Considering the iPhone 12 Mini is the first "flagship" hardware I've bought the year of release since the iPhone 4 I bought in 2010, I can easily see myself getting the same four years out of it, and probably more.
Of course I'd like to pay as little as possible for an iPhone, but when I look at how long I use the phone and historically what I've paid for iPhones in the past, is seems totally fairly priced.