Is everyone actively tracked or can the tracking be done after the fact based on ticketing, passport scans, etc? I personally have no clue if when I flew to Europe or Hong Kong I was actively tracked or not. Beyond telling my employer (the USG) where I was going, buying a ticket, and doing normal custom things I didn't do anything beyond that. Could the greater USG have found me if they wanted to based on possible emissions and travel plans? Sure, but it's not like I was trying to hide anything.
What does that situation look like for a backpacker who walks across a border or a mining surveyor who is sent there by a private company via a charter flight? What about a US citizen working for a foreign NGO like Doctors Without Borders? I personally have no idea if these folks are on the hook for an evacuation or if the evac is only for folks there on formal USG tasking.