Don't forget the lack of pallets.
And I don't think it's subterfuge like some of the nutters claim and Russians trying to hide numbers or deployments or where they are dropping off supplies to - the Scooby vans have to stick to half-decent roads which makes them stick out, are inefficient and getting Russians killed. And if they are as loaded down as they appear, they really have to stick to good roads, otherwise they get stuck.
And you know the suspension and transmission is probably shot after just a few trips of hauling weight that they were never intended to haul - those things were meant to haul packages or people around Moscow. It's been a long time, but I remember the 155mm shells alone were around 100 lbs, and those things were about two feet long and around 6 inches in diameter, which means that they are dense as hell, but somewhat small size-wise for the weight Which means some NCO or officer at an artillery battery is probably screaming at them to carry as many as possible, because even though those vans probably shouldn't carry more than 10 of those shells (and I feel like that's pushing it), in this war an artillery battery will go through 10 shells in a minute or two.
I have my issues with the Tire Guy, but he's right about American military cargo trucks maybe expensive, but they handle a lot of terrain fairly well, can carry a lot, and most/all have small cranes on the back so it just takes one driver rolling up, hopping up on top, offloading the pallets, and then hauling ass out of there. Those Russians are showing up with shells in fucking boxes, and it's taking multiple guys to unload them, and everything is slowed down, giving Ukrainian drones time to find them.
edit: it comes down to we can actually project power across oceans. Russia is having problems resupplying Russian soldiers that are 100 miles or less from the Russian border.