To entertain an actual technical discussion for a moment on this (and assuming air security is a legitimate goal), I wonder what kind of pen testing certain people might try on this, given that now there is not someone so actively watching if you display suspicious behavior. As in, at least with traditional checkpoints, an agent watching your moves could easily see if you were fiddling with something to try to evade detection. And that would deter people from trying anything.

But with an automated portal, who knows what someone might try and test the tolerances of, to understand how it works and the limits.

Although, perhaps if it is operated like some automated immigration checkpoints abroad, a dedicated officer still does oversee several booths and will probably notice lingering behavior where someone is acting suspiciously.

Imagine it's like if you knew that after 3 tries, your login attempt gets reported to root, versus if you know that never happens.