> How does free / non-microsoft software protect against a shitty decision to not update / upgrade?
By not bundling upgrades with what is essentially malware, and making them as inconvenient as possible.
If I am running Ubuntu 10.04.4, and I hear about serious malware that relies on a security hole that is patched upstream, I have the opportunity to patch it myself, and keep running Ubuntu 10.04.4 as long as I want.
That being said, it's disingenuous to compare unpatched Windows 10 with unpatched Ubuntu 10.04. It is totally unreasonable to think you are secure using an unsupported OS, but it is a lot more reasonable to think you are secure running Windows 10 just a couple months out of date.