Yeah, it's weird to talk about OpenSuse MicroOS and Fedora Atomic when they are not even the flagship desktop distros of their respective families. I guess the author drank the atomic kool-aid and thinks that's a killer feature for a consumer OS.

That said, Ubuntu is not really aimed at beginners anymore. Canonical has shifted hard to enterprise offerings over the past 5 years or so. Take a look at their web site — they barely spare a word for desktop Linux anymore. This is what you'll see on the main page:

"The complete guide to RAG"

"Modern enterprise open source"

A "Products" dropdown with thirteen items, maybe one of which is comprehensible to a beginner.

For all the hate Snaps get (and rightfully so), they make a lot more sense in the context of enterprise deployment. It's like Flatpak but for headless servers and with professional support. It took me a long time to understand Canonical's game there, because I couldn't shake the idea of Ubuntu as a beginner's distro.

I guess it would be cool to have an atomic OS designed for beginners, since the current crop are more complex than traditional distros, not less. But I don't think atomicity itself really matters, especially if you're talking about systems that are mostly locked down to begin with.

Ubuntu isn't a good choice

Ubuntu is still too complex for the average idiot who just needs a web browser.

Most Linux distros, even Ubuntu, have a "it's up to you to figure it out" mentality. ChromeOS is a "we know better than you" mentality which is honestly needed for the average Joe to keep their machine safe. Everyone hates auto updates. But lets be honest, the average user isn't going to do them unless it's basically forced on them. Ubuntu can do live security updates, but only if you opt into Ubuntu pro or whatever it's called.