They seemed to be alarmed by anyone taking an unconventional interest in station infrastructure.
Waiting for metro (marta?) I took video of a train arriving. The conductor? of the train stepped out , said that's not allowed, and insisted I delete it immediately.
I think the Overton window has shifted to the point where the ability to take a photo is now assumed to be a given, and enforcement otherwise would be difficult because "everybody's doing it".
(the original MBTA link is long gone)
I'm curious if a court has upheld that, though. MBTA is at a funny nexus of public and private organization, so personally speaking I'd like to see the First Amendment prevail.
One hypothesis is he didn't like my skin color. Maybe it was too soon after 2001.
Back then I thought this to be a very rare edge-case and it seems to be. But since then I personally witnessed persons falling into the trench twice. Furthermore I learned that railway and train operators take security pretty seriously, because anything that could go wrong probably kills you.
There were a lot of attempted strange policies about photography post 9/11 in the US. Some stuck around for longer than others. They were all absurd, not like you have to take photos to case the joint / before you set off a bomb.
At one point Amtrak had a photo contest to take photos of their trains and submit them, and a guy was arrested by Amtrack police for doing just that.
What is interesting is that after any attack one of the first requests is for people who took photos that day to turn them in so they can see if there was anything important captured.
And Stephen Colbert did a great comedy episode about this exact problem. https://www.cc.com/video/9kc6le/the-colbert-report-nailed-em... , https://www.nytimes.com/2010/07/28/nyregion/28about.html