Specifically, a good uniform must function across a wide variety of environments; see the USMC uniforms for a good example.
If we had 'active' camouflage that was updated on the fly, this might make some sense?
As for uniforms; I'm not sure any military regular with clout would be willing to do something as practical as custom uniforms based on deployment environment. Too much change, too much innovation.
Now that I thought about it some more, building a generator might be problematic because unless you want to hide toroids, there wont be a continuous mapping with reasonable amounts of distortion from the surface of the object in question to the 2D plane. That would mean that CNNs can't really be used.