I actively seek out phones that NEVER get updates. I personally hate updates. A lot of them change things that should be left alone, or totally re-arrange functions in the app forcing me to relearn everything again, which annoys me, or flatten the UI which I outright despise. Using older phones guarantees I'll never have my flow interrupted by a prompt to 'please update this app to continue using it' or be bothered by a full-screen dialog saying 'a new software update is available for you phone'
I consider lack of updates a feature. However, there's tons of FUD out there that people will get hacked just by using old software. I can assure you that unless you're stupid, that will not happen. In fact, a lot of phones well out of support completely still support some modern apps including payment apps like Walmart or Kroger, and one example is the Galaxy S5. That's 8 years of support. Android support is actually better than Apple. Since Play Services can be updated without the need for an OS update, apps will be supported even on old versions of Android for the foreseeable future, while an iPhone that is a year out of date will have many apps up and stop working asking the user to 'update to iOS xx to continue using this app'.
So while OS support is lacking, app support is not. Also, continuing to consume by buying new phones when your old one works perfectly fine (despite not getting updates) is bad for the planet. e-waste is a horrendous problem that will not be solved by recycling alone. We have to all reduce, reuse, then recycle, in that order. Also, our wallets are bigger when we stop buying new things we don't need.