I’ve got a Xiaomi 11T Pro with almost all bloat removed. VPN is on all the time and I use very strict DNS settings. I only keep it at home as a banking phone.
Should I go and buy a new one now, or can I keep using this since I don’t use it for anything else?
I don’t know what a banking phone is (or at-least what you mean by it) but it is generally advised to only use devices that are currently/actively supported.
If you can afford another device, you should get a new one. If not, I guess how you’re using it is the best way to go about so keep it simple going forward too.
Yes, I suppose so. Since it’s your secondary phone and you don’t use it every day, it should be fine to keep it for at least a few years, unless some critical security issues are found in Android 15.