It makes more sense when you understand that copyright was hardly ever about protecting authors, but about protecting the interests of the more powerful middlemen.
Having programmers sign off their copyright has the same effect as classical capitalism: it separates whoever owns the code from whoever works on it. The owners can then enjoy the full royalties, while the programmers are limited to their salaries —just like the factory workers.
Factory workers could walk away with the fruits of their labour, if only they owned the factory. Programmers could walk away with the fruits of their labour, if only they retained the rights to them. And in my opinion, they both should. The means of production should be owned by the workers, not the capitalists.
If on the other hand you agree with capitalism, it makes perfect sense to have programmers sign away their rights.
That is basically the horror scenario of backup'ing, since you don't usually protect against that kind of failure: the probability of it happening just seems too low. It's similar to having a limit to your attack model when securing your data/accounts/... against attacks: you can try to protect against a governmentally funded cyber attack on you personally, but you probably won't succeed and it's very surely not worth the trouble if you're not a very influential or otherwise important person.
In this case, the usual retort would of course be "why didn't you have a backup in 'the cloud'?" I have for part of my stuff, but not for all. I feel you.
FYI if you click that link and the referrer is hacker news it redirects you to a nice picture of a testicle in a cup, first thing in the morning.
(it redirects to : https://imgur.com/32R3qLv )
The link is fine, just don't click it from here -- well, unless cup-testicles are your bag. Pun intended.