This is one of the reasons I highly respect Xiaomi and Google Pixels. They are basically the only phones left that make this painless to do without resorting to

This is one of the reasons I highly respect Xiaomi and Google Pixels. They are basically the only phones left that make this painless to do without resorting to dodgy hacks. Xiaomi have an official bootloader unlock and are simple to put LineageOS on. Pixels are the only phones that are supported by GrapheneOS, which offers substantial security benefits over any other Android phone. It's giving the consumer freedom and environmentally friendly for when the updates run out/planned obsolescence kicks in. I have a spare phone lay around from 2014 running up-to-date 2021 Android patches and it works perfectly fine, the battery went bad once but this was the days of replaceable batts and it cost $15 online for a new one. If you can accept the tradeoff with no further physical firmware updates it's a much better deal than the rampant consumerism and e-waste that plagues the mobile market.