I"ve seen Mark's security when he's out and about on campus. They're reasonably discrete about their jobs, given that on any given (pre-Covid) day there were probably hundreds of business and personal visitors on campus.

Personal security for CEOs (never mind billionaire CEOs) is hardly anything new. If I were Mark, received the amount of hate/threat messages he does, and had a young daughter, I'd do everything short of hiring the 82nd Airborne to follow me around.

https://www.businessinsider.com/how-much-silicon-valley-ceos...

Taylor Swift once said "I don't have security to look cool. I have security because people want to take me home and chain me to a pipe in their basement."

TSwift isn't even a billionaire.