Yes most houses probably have 1 or 2 devices that have these batteries, they may or may not have screw covers, the manufacturers vary, certainly here in the UK its exceptionally unusual to simply have devices that aren't screwed down.Some interesting points. What is your argument against why concerned parents should not just put their tags in closed cases?
You could say, they can't control the cases other people use that might visit their homes. Shrugs. At some point, if someone comes in with an Airtag hanging off their bag such that a child can get to it, maybe the parent could also see it and make sure its out of reach?
Your numbers argument regarding exposure falls apart when you consider that yes, some people will get a lot, but a lot more people will get none, but almost every house has at least one device (remote) with this style battery without the protection measures you mention.
Finally, neither you nor I are design engineers. It is easy to say things like how simple it would have been for apple to incorporate a screw or what not, but I dont think its really that easy to implement in this design. Judging from the tear down, there are physical size constraint limits. So make it bigger you say. There would be safety downsides of that as well.
It's just not a perfect world. It is easier to say how others should make it perfect for us, apparently harder for us to take personal responsibility.
We were read the riot act on both occasions at hospital (2 different hospitals) when we were taking our kids home after they'd been born, the first was "no leaving the hospital without showing us your car seat", the second was "don't let your child near watch batteries", there is a major concern about them here, and the damage they can cause.
But what you said fit perfectly with my argument Apple generated the design from beginning to end and they chose not to implement a system that means a non-damaged device is inaccessible to anyone without some sort of tool, instead they chose a system that has known weaknesses for reasons that I can only presume it's because it fits with the design they were going for, they could have made the device a mm or 2 bigger, adjusted the components around to make room for a locking mechanism, they chose against it, it was a conscious design choice, and that in my eyes makes it worse. They purposefully decided that they wanted the current shape over a marginally different one (thicker, bigger, whatever) that would have made the device unquestionably safer.
Again the risks are low, if we were having 1000s of kids each year dying from these batteries they'd be banned, they don't kill many each year, they cause a lot of hospitalisations though, and it is the insidious way they can cause significant damage before the person who's swallowed it notices, or even if they do in the time it takes them to get to hospital, the device located and removed it can have caused severe harm.
The fact that the health system here and many hospitals have pages dedicated to this specific battery shows the concern, and I think it's why I find it hard to understand that people are just shrugging their shoulders. I've even had people say it's not a product aimed at me, i.e. someone with small kids, when I just see it as an absence of responsible design from Apple, they made a product that could have been 100% safe, but it's now more like 98% safe just so it looked a bit more like the original designer pictured in his head, and that feels wrong to me.