Imagine if your ISP kicked your laptop off the Internet because Microsoft stopped providing it security updates. Imagine having to buy a new laptop every 2-3 years just so you could get updates. Phones are just small computers, they shouldn't have special rules.
@fnord @kyle It's about ToS. In corp network you have your standards and even the fact of being non-compliant with standards is ToS violation. ISP may cut your subscriber's line if you violate ToS (eg detected malicious activity/abuse) but not proactively because they suspect you may do it due to using unpatched devices.
@kyle 1st thought of mine: Why Microsoft? They could use Linux resp. LineageOS. And hopefully more and more Linux on mobiles. But then I remembered UEFI and thought you might be right. I know you meant PCs were far away from phones. I don'f agree in that.
@kyle In the early 2000s, I worked in a university NOC on a software that would identify PCs that were infected with malware (mostly Blaster at the time) and cut those machines off the network until the users had fixed them.
The relevant difference here is obviously the fact that the users had enough control over their systems to actually be able to fix the problem.