It is unfortunate and annoying that manufacturers only support smartphones for 2 years with software updates, which means people feel they have to upgrade as new apps and Google Services updates start to slow down their phones. I always consider if the handset will get a community of custom ROM developers behind it so I can flash the latest version and remove bloatware.

Unfortunately it can be tricky and daunting for users who are not very technical or confident with these processes. But if you have an ailing smartphone, and you want to zap some new life into it, I suggest checking out a well supported ROM such as LineageOS, and give it a go.