How do you make money from anything on computers? With Ads, with Paid Memberships, Paid Access to content.
2) Who would buy it? Why would anyone use it?
Isn't that kind of like asking "who would buy the internet? Why would anyone use the internet?"
Remember when Chromebooks were announced and everyone laughed because it's "just a browser?!"
Well, imagine if you were browsing, except it looked like Unreal engine when you got to 3D content. Rather than looking like crappy WebGL content.
3) Is there a point beyond "this is a cool thing", which is pretty well captured by Roblox and Second Life and VRChat
Do you think Roblox, Second Life, and VRChat look as good as Unreal Engine 5?
Would you enjoy playing content in Unreal Engine 5 without having to install an entire game first?
The main bottleneck is the price of asset production. Producing assets on the level of this demo videos is magnitudes more expensive than what you would see in those other platforms. So for someone to be able to turn a profit with that, there would need to be either a bigger willingness to spend, or an explosion in player base.
There are also likely technical challenges. I'd imagine that very few people have both the storage capacity and bandwidth to sustain such a system. You see people on here complaining about websites being a few MB heavy. In such a high quality 3D browser, you would need to load multiple GBs per scene.
On the technical challenges, yes, you need bandwidth. Just like you need electricity to play a console game. Yes.
But maybe Stadia is a good way to limit how much bandwidth you really need? Load the data on the server, and stream the rendered views.
Yes you can make unending worlds in UE4.
At the same time, nothing is motivating them to do this either.
It may not be the feature list you thought the multiverse would launch with but in hindsight it will be the feature list that the multiverse did launch with.
Did HTML / HTTP have a business model? Or were they a platform upon which other things were built?
People initially tried subscription models for HTML content but it didn't work so everyone went to advertising based models. Observationally, subscription HTML content models have continued to not work (yes, Netflix, but Netflix is more about video content than HTML content).
It was a set of technologies. Advertising later came to it.
There are tons of subscription models for HTML content that you're ignoring. Patreon, YouTube, online news. Some small, some large.
You download and install it.
Then you give it a URL, and it streams down a map, and downloads DLLs containing behavior custom to that map. While you're in a map, you can walk through a portal to another map. Or you can just keep moving in a direction, which streams more and more map.
If you're in a multi-player environment, you connect to a server for that environment. If you're in a solo area, you're just running locally.
Isn't this what the Oasis (from "Ready Player One") is supposed to be like? What stops them from doing this?