Have you ever considered supporting software development outfits like [link|https://lineageos.org/|LineageOS.org|new_window=true]?
They contribute a lot to keeping old devices that don’t get software updates/ are EOL updated, secure and useful. It doesn’t matter much if you keep your phone functional by repairing it if you can’t even use it for your digital train ticket because the app needs at least Android 8. Plus, at least in my experience, it makes those old devices that might have significantly slowed down over time feel snappy again.
For me, and most people I know, the primary reason for getting a new phone is software, not hardware.
