I tried ChromeOS today, and while it looks awesome, has some really great UI elements and integrations, I would still say uBlue with KDE Plasma comes close to it.
I would prefer sane atomic updates though, like twice a month. Fedora is not that good in that regard, you want to update every day as you get fixes every day.
Also, OCI images are consuming tons of bandwidth currently, so ostree is still better.