i believe you, i was just thinking a basic flip phone couldn’t be more distracting than a 2-way radio, and i would guess they have these for comm issues.
When he was on the job, he carried a 2-way (VHF?) radio. I understood that was all he was permitted to carry. I also understand that cell coverage along rail routes can be very poor. The flip phone might not be distracting, but it might also not be very useful.