How's the battery life?

Not the parent, but my experience is very good.

Right now for example, it’s at 44% after 24hrs from 100%. This is pretty sufficient for me

I loved the 12 Mini, but battery life was one of the reasons to upgrade. 44% after 24 hours is very impressive. I often wouldn't make it through the day.

there are A LOT of settings in ios that can safely be disabled while retaining "phone" functionality and conserving energy/data

In my own experience iPhones somehow just love eating through battery doing nothing. I know because I have an iPhone I hardly use. It takes around 3 days to completely drain the battery doing nothing laying on my desk. Airplane mode does extend it by a lot. Android is much better at this, probably thanks to the "doze mode".

Adequate for my purposes. The whole point of owning it is that I have a very light-duty relationship with the phone: music/podcast, maps, some food delivery and ride share, and some messaging when I'm not at my laptop. I don't read stuff on it, let alone browse the web or doomscroll social media.

So when I'm at home it can easily last a couple days. If I'm traveling by air, or other rare occasions where my phone gets heavy use, I have a slap-pack battery to stretch it out. I'm more likely to resort to that if I'm traveling and I forget to charge it: it's obviously not as much battery as a bigger phone, but for 99% of days, it's more than fine.

It serves my purposes, and fits in more pockets than the big bricks do. I wish Apple would learn to count as low as several million, and go back to accommodating the smolphone niche, but their current policy seems to be that if a product doesn't sell enough units to supply one to every resident of a mid-sized European country, it isn't worth manufacturing. Pity.