The problem isn't so much that Google has a hard time old phones on their OS maintenance team books, and even just phoning in the effort to keep them working (hah). It's that they actively don't want to do any work that isn't sexy and supporting new products. I don't think their teams are incentivized to do so.
Let me play it out with an example.
At Apple, a team/individual might be actively told to have to use an iPhone 8 for their daily use, so they get to experience what it's like for a user with an older phone. They solve the users' pain by solving their own pain, and commit to making the experience actually better with future iOS releases. Not just keeping it working but actually making it better if possible.
Google has shown time and time again that they're not thinking like that. Or at least not setting up the company to be rewarded like that.
I will also posit that the single-handed ownership of the iOS app store makes deficiencies fall squarely on Apple, so they are more directly blamed/responsible when phone performance gets worse. With Android, and so many reasons a team could claim that other factors are causing negative trends in performance, who cares to keep making an old phone better?
I agree with the theme of your post, but I think it's often overlooked that Android doesn't necessitate full operating system updates to deliver new functionality as iOS does. Owners will regularly receive updates to basic apps such as phone, calendar, contacts, etc. through the on-going Play Store updates, even after 3 years.
This often gets brought up, but it's only because of a similar ill-discipline to what the comment you replied to is talking about.
AOSP has basic apps for all of those use cases, but presumably because it's much sexier to work on closed source in-house apps that get to be updated as often as the team feels like instead of being forced to work in the margins of the OS update schedule... they languished to the point of unusability.
I'm not even sure if they'd all run on the latest version of Android, some of them are still using Kit-Kat era UIs last I checked
It's not only that they are outdated, phone app was officially deprecated this year and I'm pretty sure it was the last one, so now android 'core apps' are officially dead
But the phone is still worthless and unable to be used once it stops getting security updates.
eg google killed my last pixel by cutting off security updates like one month before a full login bypass was discovered. I mean cute, I could still get updated apps... but anyone in possession of my phone could login as me.
It's the superior way to do it, in my opinion. I was fighting SwiftUI released with iOS 13 until last year, and will not be able to use the much improved Navigation system released in 16 for another couple of years.
Meanwhile Jetpack Compose worked pretty much flawlessly on even old Android devices.
As a former Googler who worked on some Android things I can say that this is untrue. There are many other reasons why Android devices don't keep up with iOS but a lack of Googlers using them is not one of them. There are many thousands of Googlers using outdated Android devices and there is a rich internal bug reporting culture.
Anecdotally, this doesn't match my current experience working on this stuff at Google. I see a lot of effort put into backwards compatibility.
Now I'm not talking about policies, and this may or may not be true for everyone involved, but the generalisation that this isn't being worked on or incentivised does not appear true to me.
I think 15 years is too much given how fast technology is churning.
So I think 15y might slow that down (but maybe that's good? I'm not sure). It would also probably increase prod/maintenance expenses, which would likely just be offloaded to the consumers unfortunately.
I do agree with your sentiment, though. There should be a minimum, and something like 6-8 years seems sensible to me!
Let me play it out with an example.
At Apple, a team/individual might be actively told to have to use an iPhone 8 for their daily use, so they get to experience what it's like for a user with an older phone. They solve the users' pain by solving their own pain, and commit to making the experience actually better with future iOS releases. Not just keeping it working but actually making it better if possible.
Google has shown time and time again that they're not thinking like that. Or at least not setting up the company to be rewarded like that.
I will also posit that the single-handed ownership of the iOS app store makes deficiencies fall squarely on Apple, so they are more directly blamed/responsible when phone performance gets worse. With Android, and so many reasons a team could claim that other factors are causing negative trends in performance, who cares to keep making an old phone better?