Hot take: consumer computing devices should automatically maintain enough free space to perform updates.
@wwahammy The old 16GB iPhone SE that still use at work has had this problem for quite some time, and sometimes it was only possible to install updates via iTunes due to lack of space (mostly thanks to MS Teams which keeps using up over 2GB of storage for reasons unknown) - but for the very latest OTA update it said something in the line of "I'm now going to offload a couple of apps to make space and recover them when the update is installed".
@galaxis I'm glad it worked for you!
Ironically, this was motivated by my mom having an old iPhone with 16GB and struggling to get the update installed. She couldn't get the urgent security update installed no matter what. Not sure on the specific model but I think she ended up getting a new phone.
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