The simulated conflicts are run against an adversary that is perfect. No logistic errors, no maintenance issues, no communication issues, no human error. They are a teaching tool, not a crystal ball. In reality, in the event of a conflict there are plenty of areas where China would struggle.
And of course none of these problems would apply to burger empire who would have to attack China from across the ocean requiring far more complex supply chains. I mean just look how well burgerlander proxy war against Russia is going.
Those problems would absolutely apply. And moving equipment has never been a problem in Ukraine, it has been getting permission from a fickle Congress and training Ukrainian with gear they are not familiar with.