Can a cross platform app be run as a container on both Linux and windows hosts?
But if I have a simple app like a python hello world, what prevents this from running on both operating systems?


It won't work in the same way that copying /usr/bin/python from a Linux machine to a Windows machine and using it to run your application doesn't work.

Docker isn't running the hello world script, it's running Python, which needs to be compiled for specific operating systems and architectures.