Hm I dont agree that its fine once running.

• upgrading is a total pain. I can imagine many people just dont do that at all. Like, no official documentation, anywhere you can actually find it? No automated command? Literally manual editing of a sources file?? Checking for held or not upgraded packages again to avoid breakage?
• apt is pure garbage. Nala is king, and I think they should switch.

I think a fully self updating and upgrading Fedora Silverblue/Kinoite with actually good presets would be user friendly. This means no broken Firefox, flathub, automatic updates, some services enables, some fixes here and there. Easy install, everything preset, install Flatpak apps through the GUI and forget it. Automatic upgrades should be held a month or so to avoid breakages.