Apple also isn’t dropping support for older operating systems the second a new one hits the CDNs.

A Mac on the latest OS that it can run can still expect at least two to three years of additional security updates, so if yesterday was the end of the line for your Mac and you want to use it for a couple of more years, feel free. You won’t get Stage Manager, but from the reviews I’ve read, you’re not missing much.

2016 Macs are not "unmaintained" yet. They should receive security updates for at least two more years, which will make them eight years old at that point.

They're pretty good for keeping "unsupported" devices up to date with security patches.

My iPad mini 2 from 2013 just got a security patch a few weeks ago even though it's stuck on iOS 12.