installing and setting up every month is a bit of a pain
Repent of your sins and turn away from imperative ways, for the Kingdom of Reproducibility is at hand. Convert your heart to NixOS and accept Its grace; this is not a suggestion, but a command for your eternal soul.
if you already have an esim on the phone it will not be wiped during installation - esims reside on a completely separate chip.
all "difficult to set up" information is exactly about that - setting up, that, in any case, is just about enabling specific google services that you can disable afterwards.
my phone has about 5 esims installed, I regularly wipe my phone, they are unaffected.