When I was a junior in high school and computer lab monitor, I made a suggestion that we install VNC on every computer and it was green lit by the administration. We used an app that could view thumbnails of all screens at the same time. I only enforced the "no porn" rule. Kids could play games, browse the web and I accepted fake hall passes. But if they were watching porn they would be thrown out and banned.
You're assuming it would broadcast long enough to find the station, not a hit and run operation. And even if there was a constant signal, they could be using a repeater.
His line of questioning was designed to expose discrepancies in stated policies versus actual implementation, with the goal of eroding trust of Facebook in that half of electorate. Eroding trust was the whole point that the hearing was called, and in that regard Cruz probably had the best questions. His questions were met with denials rather than "I'll get back to you on that".
The so-called "cybersecurity experts" main task in the FBI is probably running forensics on narcotics traffickers' devices and data. Using illegal drugs would be a conflict of interest.
>a density of talent and capital unrivaled in the world
The Four Asian Tigers have already surpassed SV on that. There's obviously a government-related cultural gap that won't win them any popularity contests.