While I feel that UP is going overboard, the real problem is twofold: 1. Lawyers; 2. Terrorists.
When I was a kid, I was all over the railroad yards, depots, etc. I leaned to telegraph by hanging around a depot and sweeping the floor , carrying mail bags, etc. when I was 13. Most railroaders got their start that way. That's how I got my first job working for Illinois Central in 1964.
Unfortunately, we live in a different world these days. Lawyers have encouraged people to sue railroads for accidents which were their own fault, and sadly these people have won big settlements. The terrorist threat is obvious, though again overblown. A terrorist needen't bother with a cemera these days ... a high-resolution satellite photo would show most everything they need to see.
GC is good about showing folks around if they ask first ..... but just showing up on the tracks or in the yard is frowned upon. At least half of the employees here are railfans, including the supervisors.
I lament the way things are nowdays, too.
Skip