Earlier quoted context omitted.
> The iPhone 12 and 13 Mini were always marketed as the cheaper versions [...] No, they were not. They were literally a scaled down version of their respective regular sized counterparts, the 13 Mini had the same cameras, SOC, memory, screen quality and storage options as the regular 13 [0], yet its sales success (or lack thereof [1]) was enough to instantly cure me of any previously held notions that there is a suff…
The 12 mini and 13 mini had very substandard batteries compared to the mainline version or the SE. There are a lot of people who probably would've bought the mini but instead of opted for the SE because battery life degraded so quickly.
The only thing that used less power on the mini was the smaller screen, but that doesn't save enough power to make up for a physically smaller battery.