Do people actually buy phones and start using them before wiping everything on them? I don't actually buy used phones. Too risky. But I do have a pixel. I still use it for NFC only. NFC is pretty useful. I always custom roms.
I am the one flashing a new phone with Graphene and loading the apks. This is meant for those who would like the privacy gains but aren't totally comfortable doing it.
Purism claims you can audit the supply chain of their phones. They are not very usable yet though.