Re: Attack of the sophisticated spearfishing ransomware DDoS attack ..
a) But then they won't be able to use social media.
b) Even if they did, the license key updates would still go over USB which is a huge attack vector.
c) It is very hard to have a usable, yet properly updated Windows system without Internet access. Setting up your own "Windows Mirror" is much harder than setting up your own Debian one. (Although I'm sure Microsoft will sell you an overly expensive version if you are big enough)
Other problems include internal attackers or attacks on business partners, or just general idiocity.
The big problem is that there are people who decided to build infrastructure on the systems which are hardest to defend.