But only for the latest major iOS version.

The latest version of iOS supports the iPhone 11 introduced in 2019.

And I use PCs way older than that with no issue. 6 years isn't that long

And what Android phones from 2019 are still getting updates?

Browser updates? Most of them.

The latest version of Android Google Chrome requires Android 10. But to keep getting updates you need Android 11.

Running a browser on an OS that doesn’t get security updates doesn’t sound like a winning combination.

More winning than updating neither