That's not really how it works in practice in my experience. In some time, some thing you use needs to be patched and the latest version only runs on the newer platform.
Doesn't matter if the underlying platform is supported if the entire ecosystem moved elsewhere.
Here's probably a silly question: Shouldn't this work automatically? I just assumed they would have an intermediate CA or whatever it's called and have that certificate be signed by some widely trusted CA.
Or have they done it in a different way for security reasons?
Sorry, but I'm not sure what point you are trying to make here. Is your scenario that the users license to use the OS is revoked combined with there not being any backups?
If you store data on a computer without backups you can expect to lose that data. Disks breaks, files are corrupted, computers are stolen, node.js deletes your crap. Or whatever.
As for employees embedding stuff in OS code. Sure, that can happen. Open source developers can also embed such code into any code they write, which has happened many times already. Unless you are writing your OS yourself from scratch or manually reviewed all source code for all code running on your machine (which I suspect no one has done the last decades), this is a risk. Open source or not.
I never touched Bitcoin so maybe you can clarify how this makes sense:
> If Microsoft decides to terminate your license, what happens to your Bitcoin?
Your Bitcoin is represented by some kind of data stored on your computer I assume. So this data should be backed up, right? So the anwser is that you would access the bit coins from some device which you have a license to use?
If my understanding is right then I would consider the quoted statement to be a bit FUD:y.