Is the setup_python_env.sh file which gets called by python.sh set programmatically by Isaac Sim, based on the activated extensions? Or is it something where the dev team/the end-user just adds the extension paths into that script and saves it?
At the moment its hardcoded to contain paths to all of the extensions that ship with omniverse and isaac sim. So yes you would modify it manually to add an additional extension.
Will add this as a feature request, and otherwise at least document the process of adding additional paths if there is no automated way of adding all paths at runtime.