Any hindrance we can put on the Finnish-Russian border to stop them just unloading 12 cars of fresh troops in the middle of the country is a good thing.
(Of course a more thorough analysis would probably come to the conclusion that better logistics is worth it. There's still an opportunity cost for those conscripts who could do something else instead, like dying in zerg rushes on the Ukrainian front. And even though those conscripts are 'free' they still require chow and a place to sleep etc.)
Now you’re just being silly.
Related, I have seen one guy, over and over say "Why isn't Ukraine hitting Russian electric train transformer stations". I don't have a good answer, most of Russia's rail network is electric, transformers blow up easily, there are many of them, and they would be very slow to replace. Ukraine clearly has deep strike capabilities, and Russia cant defend every transformer. I don't think it's a humanitarian issue, or at this point even an issue with the US telling Ukraine they can't hit those targets.
I would compare it to the Natanz cyber attack which reportedly cost a fortune and caused lots of business losses around the world. It only set the Iranian uranium refinement back a few percent.
Then Obama comes and talks to them, strikes a deal. That solved the issue entirely and cost much less. Of course then Trump comes and messes it all up again but that's another story.
https://www.nti.org/education-center/facilities/natanz-enric...
So I stand by my statement that his assessment is not wrong, even if it isn't as outcome changing as some may hope. It is however one of the many straws heaped upon the camel's back.
As for the transformer issue, I would imagine that these are somewhat related. Their train based logistics are inefficient, so Ukraine doesn't need to stop the trains running. If they did the russians may find a more efficient solution.
Even Unicef has a massive logistics center in Denmark with pallets of stuff categorised and ready to be sent for any emergency: https://www.unicef.org/supply/warehousing-and-distribution
Russia just likes to kill the shit out of their neighbours which is a lot easier logistically.
Those few connections in the sparse north of the country are the entire point.
Of course, if it does go that far, tanks and trains can move rolling stock, rip up the tracks, blow up bridges and other infrastructure behind them if they're forced to retreat.