I've spent a decent amount of time looking at Dynamicland-related things, and it seems consistently grandiose + vague. Maybe it's just that the material they're putting out is more for investors than other hackers. Not sure. The language rubs me the wrong way though:

Dynamicland is a communal computer,
designed for agency, not apps,
where people can think like whole humans.

It's the next step in our mission to
incubate a humane dynamic medium
whose full power is accessible to all people.

Just take "designed for agency, not apps" for example. It's a nice rhetorical technique to contrast apps with agency like this, suggesting that apps somehow deprive one of agency and that Dynamicland can restore it—but it feels pretty disingenuous if you think about it for a minute. (There's a section on the page also titled "Agency, not apps", which brings me no closer to feeling that the use of 'agency' is justified.) In actuality each platform (traditional computing, Dynamicland) has tradeoffs in terms of what one's agency is applicable toward. I can see no reason to think Dynamicland is an increase in agency over traditional computing rather than a lateral (and perhaps complementary) change. I agree it's nice to use your body rather than just fingers, but unless I can do the same things with the 'alternative medium' (and there is no material I've found suggesting a level of generality even in the same realm as traditional computing), I'll complement my computer use with other physical activities and face the reality of fingers for input until a true alternative comes along.

I agree the problem they are addressing is epic, and their language is suitable for describing it, but from what I'm able to glean about the project, the solution so far is on the level of 'neat,' and maybe important for introducing new users to programming—but, if that's what it's for, just say it! Instead we see that the aim of the project is to 'reinvent computing for the 21st century'. So am I going to do my taxes with this? Am I going to use it write novels? To design 3D models? To conduct research? To build artificial intelligence? To discover new medicines? To call an Uber? Is there any reason to think it might attain the level of generality where it could at any point be an actual alternative to contemporary computing? Or are we supposed to take this on faith because of the people involved? How could this compete with similar systems designed in AR? It seems to me like there's more 'agency' in AR since a system like this could be replicated within it, but with AR we'd likely have a number of alternative 'physical computing platforms' like it (Of course not soon, but they're talking about a timeline of at least 50 years for this project).

It's definitely refreshing to be able to interact with 'real' objects ('physical' would be less rhetoric-laden), but I feel like the novelty and suggestive language here may tempt readers into forgetting how much power was gained through computation specifically because it didn't require fiddling with physical objects. It's a big deal, and I'm pretty sure that a legitimate alternative computational medium will require deep theoretical breakthroughs, of which I've seen no suggestion here.