Environment variable is not passed to ShinyApps.IO app

I have a Python Shiny app that looks like this:

from shiny import App, ui, render
import os

app_ui = ui.page_fluid(

def server(input, output, session):
    def my_text():
        return os.environ['BOOP']
app = App(app_ui, server)

And I deploy it to ShinyApps.IO like this:

rsconnect deploy shiny . --name myname --title your-app-name -E BOOP=test

The environment variable does not get printed as expected. Now, say I specify it in my local environment before deployment:

export BOOP=test
echo $BOOP
# test

And try ,

rsconnect deploy shiny . --name myname --title your-app-name -E BOOP

This also does not work. However, if I modify my app to access the PATH variable (which I know will exist on the server without me having to set it) I can see that variable just fine, so the issue isn't my code accessing environment variables.

Why can I not pass an environment variable using the methods described in the reconnect deploy shiny documentation?