https://en.wikipedia.org/wiki/Find_My
tl;dr Apple devices broadcast IDs and then other Apple devices phone home with those IDs and GPS locations so the owners can find their lost devices even if they don't have internet connectivity.
Most of users want a way to find / lock / remotely wipe their 1000$ phone in case it gets lost or stolen.
It's really useful for locating lost headphones, laptops, etc. -- whether stolen, left on public transport/taxi, or left at a friend's house.
Edit: link to Apple's description of how Find My works: https://support.apple.com/en-gb/guide/security/sec6cbc80fd0/...
Would have been nice if the article explained a bit what is actually happening. The wikipedia article doesn't mention it either...
That's right - you can read more at [1]
1: https://support.apple.com/en-gb/guide/security/sec6cbc80fd0/...