Is the benefit transferring "local" via BT instead of across the internet as a text message attachment? Because I do the latter plenty, but pretty much never AirDrop anything to anybody, even if they're sitting next to me.
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.
I used them. Compression is an issue in other protocols (sending via WhatsApp, for example). Another benefit is that photos sent by Airdrop get automatically backed up. It also works well in areas with poor internet connectivity. For example, some beaches have weak cellphone signals due to their surroundings, so when meeting friends, we generally use Airdrop.
I'm sitting in the beach with no data connectivity whatsoever, much less any WiFi network anywhere close; my partner just asked me to send a copy of the photos we just took with my phone 10 mins ago. That's the use case. Not outside reach of a WiFi or 4G network much for you, then?
Another easy example of use case is wanting to share a file during a flight or while being overseas on a boat.