As you can see, I use the cmd you provided to install pkgx, but fail.
Then I simple run the cmd irm https://pkgx.sh > pkgx.sh to see what happen. And here is the code in pkgx.sh
Somehow, the download link redirects to the webpage where the GitHub repository is located.
I guess this is a bug. Please fix it.