You do know theres a probability the battery has the same coating a nintendo switch cartridge has right? That makes it bitter to avoid these problems. Kids can ingest all sorts of things.It's not about personal responsibility it's about poor design, if you build an item that is designed to be attached to items to help you find them, which means that the purchaser loses them at least enough to decide spending ~$45 on an AirTag + case is money well spent, and you decide to use a battery that has a reputation for seriously harming young children and animals, and then you decide to make a device that has tool-less entry, that's pretty damn negligent, especially when the decision to not include a safety screw is not a functional decision at all, it's purely aesthetic as you don't need regular access to the battery compartment ~once a year according to apple.
A battery is the least of a kids damn worries. Or stick the kid in a bubble. The world is a dangerous place. Thats life.