I use Kinoite over silverblue and other Fedora versions simply because of the desktop. I choose Fedora atomic over other immutable distros because I simply think it's the easiest/most convenient. VanillaOS might be pretty good, but from what I can tell it's on an Ubuntu/Debian update schedule which isn't what I want. I tried NixOS but it's complexity just wasn't appealing.
I use Bazzite over Kinoite because it has all of the tweaks I want, honestly the amount of "bloat" isn't as crazy as you'd imagine.
I don't have any resources about distrobox unfortunately, but I'm sure they're around.
This feels like a step back from what we currently have.