What inactions? Apart from creating safe conditions beforehand (but perhaps that is your point), once my kid is asleep there's not much more I can do? Most of that time I'm sleeping myself.
Exactly, there's not much more you can do when you're asleep. However, this system might just nudge you awake if something happens when you're asleep. Or it won't and you would be no worse off than if you didnt have it.
It's not going to solve all problems.