It makes less sense since extensions actually ran on Android, e.g. via Nightly and creating your own list of exceptions. Also if you downgrade and install in an old Fennec version, extension will continue to function if you then update to the latest.
I think the move was an attempt to create a walled garden. But for whatever reason, they have now decided against it. Thank goodness.
Search for "how to install Firefox in Arch". Snapstore page which asks you to first install snap from AUR, and then install Firefox through Snap is the second entry, I kid you not!
And they have same pages for Fedora erc.
This predatory behavior is to try and get any potential new Linux users to use their crapstore instead of their distro's package is disgusting and malicious.