It's just placed in the ear and could fall out.
Question: do the regular earpods ever fall out of your ears?
If no, then you probably won't have that problem with the airpods either.
If yes, was it because the attached cord got snagged on something?
If yes, then do you really think you will have much of a problem if there is no cord?
If no, then simply buy something else (or nothing at all.)
Is it really necessary to keep on re-posting the same alarmist handwaving incessantly in post after post, though? People know your opinions by now, and you're just repeating yourself (perhaps in an attempt to convince people to your personal opinion.)
As for me, I've never had an earpod fall out spontaneously on me, and I use them all the time. I've never found a pair of silicon-tipped buds I've liked very much, they all feel as if they're not fitting properly or not forming a proper seal. Earpods have been the most comfortable buds I've ever used, and I started out with Sony Fontopias in the 1980s so I've had time to try a few since...
I've also tried behind-the-neck corded bluetooth buds, and the cord snags on winter clothing, the collar of my shirt/sweater, and my hair, yanking annoyingly on the buds and causing noise in my ears.
Incidentally, earpods actually do sound pretty good if they fit your ear well, as they do mine. If they leak, well, obviously there goes your bass response. Being completely cordless, I expect airpods to fit even better than regular earpods since there's nothing pulling on them all the time, and thus sound better. Hopefully I will be able to buy my pair tomorrow (monday.)