My OnePlus 3T from 2016 still works perfectly fine, I’d say a normal 3 also would. That’s a more than 7 years old phone. Good Android phones don’t randomly stop working, except the cheap ones that are already underpowered at launch.
Oh I didn’t realize Google was still letting you update those! I heard all those stories of being locked into ancient android versions.
Well OnePlus doesn’t, it’s running Android 9 while Android 14 releases in a week or two from now.
(The OEM makes the update for their device, not Google.)
However, unlike Apple, you can still use “ancient” (perfectly usable) versions of Android for many, many years if you accept the security risks. Apple just makes the device useless because apps on the App Store require a newer iOS version, while Android apps usually target something from 2015 (Android 5+) or 2017 (Android 7+) as their minimum suppoeted version.
The big question is if you should use the device. Theoretically it’s unsafe, in practice the vulnerabilities aren’t exploited in the wild if you don’t go looking for them.
I use a Pixel 7 as my main device and I can tell you, functionally not much has changed since Android 9. The OP3(T) from 2016 would be fine for most people for at least another 2-3 years.