I'd like to show a slightly Inception looking way you can install RPM Fusion in a way that you don't have to worry about needing to remove-and-reinstall it with every Fedora update.
The issue lies with the "normal" method of installing RPM Fusion being specific to the currently installed version of Fedora. We'll remove this specificity by relying on the repository packages the RPM Fusion repository itself actually provides.
First, let's install both RPM Fusion
nonfree repositories using their recommended way, if you've not done so already:
❯ sudo rpm-ostree install https://mirrors.rpmfusion.org/free/fedora/rpmfusion-free-release-$(rpm -E %fedora).noarch.rpm https://mirrors.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-$(rpm -E %fedora).noarch.rpm
Next, reboot your system. This is a required step.
Now, after rebooting, we'll both remove the specific package version we just installed and install the "automatic version matching" versions available from the RPM Fusion repositories, all in one fell swoop:
❯ sudo rpm-ostree update --uninstall $(rpm -q rpmfusion-free-release) --uninstall $(rpm -q rpmfusion-nonfree-release) --install rpmfusion-free-release --install rpmfusion-nonfree-release
And that's it. From now on, your RPM Fusion repositories will correctly update alongside your Fedora updates. Pretty neat, right?
I hope this helps!