No, probably not, sounds like you, like many, have the PC overloaded with all manner of *** running at start up. What do you mean by "crash"? how does that manifest itself?
The internet being busy or even overloaded would result in slow load times for pages or even time out on connections to new tabs but should not cause the pc to crash.
no, the world using more internet shouldn't cause that sort of thing to happen to your PC. Just possibly it's been infected by a non-corona virus of some sort. Do you have an anti-virus or anti-malware programme?