I have ADS-B in my airplane and can see everything on the ground on a pretty map as if it were literally a video game. I can see landing aircraft in realtime while holding short or crossing a runway. The emergency responder should have had it in their fire truck.

The technology already exists. The problem has already been solved with an iPad and a $200 receiver. Almost certainly some BS regulation or rule was at least partially responsible here.

Well imagine if we designed a TCAS-like system that did work below 1,000 feet!