Take China for an example. No one knows China's true military capabilities, because they're rapidly evolving and because they virtually never use them. If there's an element of surprise to be had, they have it. But that cut's both ways, because China itself doesn't have experience exercising those capabilities. The learning curve could be noticeable. Meanwhile, no one doubts the ability of the US military to execute.
China uses wars like these to test their equipment for example the s300 knockoffs. These were not effective in Iran nor in Pakistan. I am sure the Chinese have made a note of that and debugging the failure.
