Fair enough, but the wiretap laws are all phrased in terms of "conversation participant" -- a listener who every speaker is aware is listening. Some states require consent of all participants, others require consent of one participant.

In one-party states the consenting party has to be the one who makes the recording. In all-party-consent states, the verbal declaration that a recording is happening has to be part of the recording. It has to be verbal, so there is no "fine print loophole" -- you have to waste 2-3 seconds of everybody's time saying it out loud.

I like your idea, but the wiretap laws work so smoothly because they bootstrap off of things like "conversation participant" and "verbally granted in the recording itself" that don't carry over to location data.