Upstream images vs bazzite: https://github.com/ublue-os/countme/blob/main/growth_upstream_with_bazzite.svg
My prediction: bazzite may have more installs than Fedora KDE by the end of the year.
It's better to think about it as though you are making a queue of changes that need approval to be permanent. Rather than just accepting that you just installed a ton of dependencies for no reason because you didn't really want the software, you can cleanly reverse any of the changes.
In a sense, it accomplishes a similar thing as nix in a different way.