Your choice is making sure to buy a well supported, timely updated device. If you can't is a different issue. But, if you don't is on you. Vote with your wallet.
Your choice is making sure to buy a well supported, timely updated device.
Sure, that choice is currently available, but it wasn't when many of those devices were purchased. For example, I'm currently using a Galaxy S10e which had just about the best support of any Android phone. Now I'm stuck on Android 12. I actually planned on using it with Lineage, but somewhere between my S7 and the S10e, Samsung stopped using Exynos in their Canadian phones, and I didn't realize it. The hardware is still more than good, and as others have pointed out, with Play Service updates, the software isn't really obsolete either, it's just a concern I'm not getting security updates.
As long as my provider is selling me service for the device then they have a responsibility to support it and provide upgrades. I do vote with my wallet by not being on the upgrade treadmill.
Newer smartphones are supported anywhere from 6-7. Fairphone being supported even higher. Unless, you are saying that's not enough in that case custom roms are your 2nd option after official support.