You can! Android is a Linux based operating system, which means it is easy to modify. The short version is you replace your Android with a modified Android. The new Android does not play by the rules: zero bloatware, very customizable, and you can update regardless of hardware.
Google the phrase “how to install custom ROM Android”. You don’t have to be a super hacker, there are plenty of tutorials and it is not an uncommon practice.
If you wrote custom android drivers for the older hardware, you probably could. There are many new layers that due process more in newer android versions though, so it would likely crawl through some tasks, and possibly find others unavailable (5guwb).
Also there’s planned obsolescence, where hardware company’s only support their hardware on newer software versions for so long.
But the eli5 is because the juice isn’t worth the squeeze.
In most cases there’s zero reason why they can’t be updated. The manufacturers simply choose not to, as part of the plan for each model is to have it have the shortest lifespan possible so we can create more e-waste by buying more devices to line the greedy pockets of the slime bag companies who perpetuate this behavior.
It’s a big part of why the planet and everything on it is in the process of dying.
Microsoft is now starting to do the same thing with Windows and PC’s.
And once they started figuring out that people would continue using their old phones as long as possible even after the software updates had stopped, they turned to making lithium ion batteries intentionally less robust so that they would fail early and potentially render the hardware useless more quickly. Only problem with that is that lithium ion batteries can swell and become fire and explosion hazards, so they are essentially putting our lives at risk to force us to buy new hardware more often.
It’s amazing how I still have some old tablets from like 10 years ago with zero battery swelling, and the batteries still charge fine and hold a charge even when left in a drawer for many months unused. But a modern smartphone battery will start to swell in just a few years, and degrade to the point where the runtime is so short that it becomes almost unusable. It’s all by design.
Get used to it, because it’s not going to stop.
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