I used eSim for a while when I first got a phone that supported eSim, because I wanted to make it harder for a thief to disable the phone tracking, but now my main phone is broken and I'm a bit annoyed at having to chat with customer support for half and hour to activate eSim on another device.
eSIM because I can install multiple of them in my phone and swap as needed.
I keep all the eSIM data stored in 1Password so whenever I change my phone or anything at all, I can easily download and install them to another phone too.
You can store them in a password manager? My carrier just ask for the imei and you get a notification to add the eSim. There is no way to re-add it once you remove it so theres no useful “data” that I can store. I’ll have to ask them to re-add it after deleting it.
I never have to scan any QR codes for my carrier, but I’d assume those aren’t gonna let you re-add the eSim anyways so there isn’t really any point in saving those QR codes.