RR's are extremely vulnerable, but Ukraine has done a fair job of keeping theirs running, albeit with a lot of electrification down.
As to what might happen when Russia goes to war and is losing?
Putin's nightmare
And if you are looking for a private car trip?
Private Car Fan Trip On the City of Moscow
And, I found this: The locomotives seen in the film are Spanish locomotives like the RENFE Class 240 (ex-1400 MZA), and Strelnikov's armoured train is towed by the RENFE Class 141F Mikado locomotive.