There could, in theory, be a malicious machine on the internal network that was previously infected, which is now acting as command and control. So if you didn't know which one it was...
That's generally a good idea, however, there can be reasons not to do it.
The device could be infected in a way that it won't turn on again.
You might have an isolated management network that allows you to monitor the device and traffic (naturally ripping all cables also disconnects the management network).
You two are overlooking the most important thing. It might be fun to crazily rip out the cables then make a junior guy go trace and repatch it all. The opportunity to legitimately do that doesn't come along often.
Depends. If you're at home with a single endpoint, maybe.
But in cases like the image there's a lot of internal traffic and you'd want to stop the malware spreading internally. There might not even be internet connection at all.
Most serious infections are able to work within isolated internal network. You can stop data breaches by cutting external traffic but if you have ransomware you might want to cut internal connections too.
You might be able to stop the ransomware from triggering on some devices. That of course depends on the type of ransomware and whether it's triggered based on time, external command or something else.
I think that's rather odd comment. Naturally nobody wants ransomware. And there are good reasons.
Backups may exist, but do they work properly? Or are the backups encrypted too?
How old are the backups? They might be less than a day old. But less than a day might still mean a lot of extra work and financial loss.
There might be a lot of work restoring the backups. You might have a lot of different systems.
In one of the largest ransomware cases in history, Maersk worked for months to get systems back up and running and data up to date. The insurance payout for it was 1,4 billions. Which is at least indicative of the cost.