Passkey is some sort of specific unique key to a device allowing to use a pin on a device instead of the password. But which won’t work on another device.
Now I don’t know if that key can be stolen or not, or if it’s really more secure or not, as people have really unsecure pins.
This and if any business anywhere manages to reache a significant level of success — and has the nerve to charge money for their service — it’s a sign that capitalism doesn’t work and corporations are inherently evil.
I just assume it’s an age thing.