Ideally the TSA at each airport would measure it and release it. They should be measuring it anyway since they should both have efficiency targets for how much of a delay they introduce, and also so that they can show data about how much or little inconvenience they cause when DOGE finally comes to cut one of the actually utterly useless government expenditures.

Since the TSA doesn't seem to be releasing this data though, apple or google could spy on GPS and motion data for individuals to estimate when people entire the line and pass through security, and derive a better-than-nothing estimate. It does seem like the government refusing to do something, and apple/google stepping in and doing a government-like thing is a norm, so even though I'm joking I wouldn't even be that surprised.