Lots of comments come up here every time TSA facial recognition makes the front page asking what the difference is between this and the human looking at your ID.

The answer is what happens when you don't match. I have long hair and a beard in my driver's license photo. I don't now. The license I had before I was able to renew without ever having to go in person for 15 years because of holes in California's laws about renewing driver's licenses remotely for anyone who has ever served on active duty military out of state. I have very rarely had a driver's license photo that actually looked like me, and TSA agents have commented on it pretty frequently, saying I don't look like the person on the ID I'm presenting. They let me through anyway, because what else are they supposed to do? Identification cards are in and of themselves somewhat of an element of security theater in that sense. The data are frozen in time whereas reality may constantly change.

The only reason this was ever the case was the fact that your identification photo was not regularly updated to match your current face. If the TSA is constantly taking more photos of you, then potentially it can be. The obvious next phase in a program like this is to store the photos and build a current and updateable model of what every person in the US looks like, eventually not needing the ID cards at all.