AirDrop uses P2P wifi for the actual transfer which can make it significantly faster than transferring through the internet, which makes a big difference for photos, videos, and other large files. It also works out in the middle of a forest where there are no wireless connections as well as it works in the middle of NYC.
My son regularly borrows my iPhone 14 Pro for shooting video, and I inevitably have to do a large AirDrop transfer to him of all his footage. We usually see about 10 GB per minute, which is really fast
If it was a few large files as opposed to many small ones, this is totally believable. iPhones have Wi-Fi 6E chips, and an ad hoc network where the devices are right next to each other can actually reach the theoretical max speed of the protocol (as opposed to real-world connections to a base station, which never do). I've never measured it precisely but I've transferred ~1 GB disk images over AirDrop in a couple seconds.
