Taking away freedom is always about "saving children's lives". It's so common in fact that the instant one hears about "saving children's lives" we can be certain something very bad is going to happen.
I am not a big fan of copyright myself, but calling being unable to use someone else's story for yourself "taking away your freedom" is a bit too much.
Isn't it obvious where this could be going? Let's save more children's lives by making all copyright infinite.
I mean, no? There is absolutely no indication that that particular slippery slope is being slid down. Can you even point to anyone advocating for infinite copyright on all works on the basis of the Great Ormond Street example?
Not if you really believe in the concept of public domain. Old stories should belong to everyone, not "someone else".