I've been an SRE before, and have kids. I don't think there's any real expectation that a baby monitor is a reliable alerting system that can be depended on. There are definitely people in the thread who believe that's the case, and it also looks like some products are built to those high standards, it's not legally required, and I don't think it's even desirable.
I don't hold the people who care for my children to the standards that you would hold a video camera (IE, they're allowed to go to the bathroom with the door closed without alerting) so I can't see why I would expect it of the technology that approximated it.
I agree with the sentiment here; there seems to be an impression that a baby monitor is a safety device. I'm not sure it is.
We use a baby monitor during naps and overnight. It's a good way to relay any noises and reassure us he's ok, but you can't really see enough detail on an overhead camera to see they're breathing or anything like that. It failed a few nights ago, and we woke up when we heard the crying through the couple of doors. (If we were awake, downstairs and it failed, we would have tried to fix it pretty quick, but we have the fairly basic backup strategy of going to sit upstairs with him.)
I don't hold the people who care for my children to the standards that you would hold a video camera (IE, they're allowed to go to the bathroom with the door closed without alerting) so I can't see why I would expect it of the technology that approximated it.