Russian Armored Trains - Today - Trains Magazine

The first thing that I thought when I saw this somewhat propragandistic video was "they learned nothing from the Winter War".  One penetrator on the track in front, one behind, and there they sit while the drone PGM or remote strikes roll them up from one end to the other -- machine guns and artillery not much use.

But what that train is doing is something different -- keeping the rail line protected from sabotage by partisan-like groups.  See him scanning the track ahead... on foot... for IEDs or sabotage heat signatures?  See the machine gunners looking like low-altitude versions of Huey door gunners?  A tank for a bit longer turret-equipped force projection where the machine-gun rounds don't reach.  Cheap and easy to run up and down to keep the supply line protected, and presumably to defend some of the freight logistics movements over the line.  In that role, it makes somewhat better sense.