I have no idea why you're trying to argue with me over absolutely nothing. You could have saved so much time by asking questions instead of accusing me of things I haven't done, and spreading misinformation about it.
CUDA support in Docker requires nvidia-docker+nvidia-container-toolkit+libnvidia-container, and that is the whole point of having nvidia-docker installed. We validate that CUDA functions inside of Docker when pushing updates to nvidia-container-toolkit and friends.
Tensorman is not a replacement for nvidia-docker, and you're not going to get anywhere by trying to convince me about the functionality of something that I personally wrote. It is quite literally just a simple command-runner that runs docker commands, specifically for the purpose of managing the official Tensorflow Docker images, and getting a more streamlined setup for managing your local Docker images based on them. The sole purpose is to replace our previous tensorflow packaging in Pop!_OS that became impossible to package because newer versions of Tensorflow did not build beyond 18.04. Tensorflow themselves recommend using their docker images instead of trying to package and install their libraries on your host OS.