Their utility is directly tied to how many Apple devices with gps and data are in close proximity to them.
I get significantly better responsiveness from them at an Australian airport or Singapore airport than I do at Bangkok airport. That doesn't mean they don't work, it just means it's unrealistic to expect minimum wage baggage handlers in Thailand to have an iPhone in their pocket.
What about baggage handlers at two major US hubs where this bag flew? Plus presumably an entire plane of iphones and that plane is certainly not a faraday cage.
Its crazy, but sometimes people have non-Apple devices. There's a decent chance none of the baggage handlers had an Apple device on them when they were handling the bag, or they were only around the bag so briefly it was between the airtag's chirps.
There's a good bit of separation between the cabin and the cargo hold. I imagine it could be pretty difficult to get a read from a low power tag deep in a bag in a pile of other luggage with several other big metal plates between.
I get significantly better responsiveness from them at an Australian airport or Singapore airport than I do at Bangkok airport. That doesn't mean they don't work, it just means it's unrealistic to expect minimum wage baggage handlers in Thailand to have an iPhone in their pocket.