Not sure where you got that, my iPhone 6 was still getting OS updates last year (mostly security ones). I didn’t have any issues with the App Store either. Now there were a few apps like Pokémon Go that the phone couldn’t handle, but that’d be true io any old PC. Devs gear their apps to the larger percentage of devices so they can leverage the newer tech. Progress is what it is. Devs aren’t going to code for a 10yo phone if 0.5% of people have it.

That’s true, but this happens because usually 95% of people are always on the latest version a few months after the new version was released. For developers, it’s really not worth supporting older versions when the overwhelming majority of users already upgraded.

Still, many large companies still support older versions when the user base is very huge. I work for a huge bank and we had to support all the way to iOS 10. Only this year it was recently upped to iOS 14, which now covers probably 99.99% of users.

Don't forget you can get 10+ years of software support through third party devs

LineageOS comes to mind

And if you stay that many versions behind, you carry a gold mine of vulnerabilities that can be exploited. Your phone might work, but it’s far from a safe or good idea.

Android and iOS developer here. Web and app.

I have so many damn phones floating around my damn desk. I have near old iOS devices that are still solid for web browsing.

The bigger problem is that mobile processors saw MASSIVE performance changes over the past decade, and apps that are developed for new silicon run like shit on old ass hardware.

In other words, performance with new apps is the pain I feel first. Browsing the web on an old iPhone 6 is generally fine.

I'm on Android 9 and the only apps that haven't played nice are a couple banking apps.