This is not an operating system, this is a UI, and as far as I can tell, a non-functioning demo at that. That's fine, great actually, but let's at least use the correct words.
Purely aesthetically, this is great. It's incredibly Apple-ish and honestly just seems like a massively simplified alternative to iPadOS -- SiriOS, maybe? -- but that's not a knock, it's extremely polished and overall fantastic design work.
But just because it's nice to look at doesn't mean it's nice to use. The predictive nature honestly just seems annoying -- there's a reason people curse at their voice assistants so often. It's a gimmick that I doubt will ever be as useful as we'd like, at least not until AI takes a massive, massive leap in the direction of Jarvis and the like.
My problem with these kinds of "declarative" approaches to user interaction -- anything that obfuscates the "how" things are done because apparently that's too difficult and scary -- is that it tends to encourage passive consumption, not active creation. Or, at best, you get toy creation apps that piddle around in the absolute most basic of the basic such that really they're better classified as educational apps rather than creation apps.
For a totally consumption-oriented device, that might be fine for a while, but eventually I'm going to disagree with either the direction a developer has taken an app, the content it's curating for me, etc, and will surely want to deviate from its "curation" in some way or another...however, this experience looks to hijack so much control from the user that they can't configure anything. You're either along for the ride, or you don't use the device.
I said this in another comment, but it bears repeating: computers are not going away, therefore computer literacy is a facet of literacy in general. And IMO literacy is a basic tenant of being free. I for one would like to see designs that give users some agency in their devices and aren't condescending in the name of offloading the "inhumanity" of...thinking about where you put your files. Come on, that's just absurd. I get what Jason is going for here, but it's completely jumped the shark from Silicon Valley into HBO's Silicon Valley. He should remember Steve Jobs' quote, that a computer is a "bicycle for the mind." The really important thing about that quote is that it's not a car, and it's certainly not a self-driving one. It's a bicycle -- it augments and multiplies what we put into it, but we still have to put something into it. If we're not in control, then who is? I would argue that it's those who are feeding you the content that you're consuming. By losing the ability to "grip" your device and actually exert some agency, and perhaps use it to create something new and novel, or at least to actively explore, you're making it so that those for whom these designs become "what a computer is" will have to climb that much higher in order to even begin to understand how to transcend the content feed, one example being that there are kids starting computer science programs today without even really understanding the concept of a filesystem, because they've never had to interact with one beyond maybe Google Drive. They're mistaking the cave for reality.
Anyways, it's late and I'm not sure how to end this rant other than by simply stepping off my stool, so -- step.