Web standards have progressed but your other points would still apply.
Does there exist a company or project that has the resources to develop a smartphone with better performance, UI, and cost than Android or iOS devices? Microsoft couldn't pull it off, and I am skeptical that Meta would have been able to.
I can imagine an alternative smartphone carving out a niche audience like older users, FLOSS enthusiasts, digital minimalists, kids, gamers, privacy-focused users, etc. Perhaps over the span of decades such a project could iteratively improve while the incumbents enshittify and eventually surpass them in popularity.
But it seems more likely to me that Android and iOS will dominate consumer smartphones for as long as that form factor exists. When they are displaced, it'll probably be by some innovative non-smartphone computing device.
Nobody was wanting to pay for and deal with the Microsoft lock in.
A new web-centric OS could fix those issues by doing a few things to reduce friction.
First, use an Android-compatible kernel version so drivers are easy to port. This gets manufacturers on board.
Second, make your App Store a non-profit that charges enough for ongoing store development and distribution. This gets devs on board.
Third, make sure you have decent third party framework support. Flutter, react native, and maybe even an Android runtime that legacy apps can integrate into their wasm binary. This helps kickstart your ecosystem.
Fourth, add better integration of webgpu and 2d canvas (which probably needs some extending). In addition, they need to add a low-level API to access DOM nodes from wasm. For security and ease of implementation (without stepping on the toes of the normal standardization stuff), this would probably be a virtual DOM with only a provably secure subset of the actual nodes being sent back and forth.
UI is an easier problem. The best design to date is still webOS. Copy their general design (maybe rip off some of their never-shipped mochi stuff).
The biggest issue as you said is financing. All these things turn into lots of developers and time. The best bet here would be replacing something like Tizen where a corporation is already investing.
Developers are typically motivated by net revenue which is more dependent on audience size than fees. That is, if you sell an app for $1, would you prefer to earn $0.70 on a million downloads or $0.99 on a thousand? (With the former you can buy a house, with the latter you can buy a laptop.)
And as you've pointed out, implementing support for third party frameworks and funding improvements to webGPU, wasm, etc is expensive. Even recreating the webOS UI would be a considerable undertaking.
> The biggest issue as you said is financing.
Exactly. I agree that it is technically feasible, my point is that it is economically challenging. Not impossible, just extremely unlikely.
> The best bet here would be replacing something like Tizen where a corporation is already investing.
It looks like the last Tizen phone was released eight years ago and the Tizen app store shut down four years ago. Like webOS, it lives on as an OS for TVs, but I am skeptical it can rebuild enough momentum to challenge Android or iOS.
> Second, make your App Store a non-profit that charges enough for ongoing store development and distribution. This gets devs on board
You're hilariously underestimating the difficulty of getting the dev/user flywheel started: developers go where users are, and users won't adopt a platform without the apps they need. Microsoft was literally paying devs for submitting apps, and they mostly got variants of Flashlight apps, and none of the apps that matter. Look at the top 10 App Store/Play Store apps and ask yourself if the developers will bother with a hypothetical non-profit, upstart
I didn’t say it was easy, but what I listed are to me the best ways to reduce as much friction as possible.
AsI recall, Microsoft wanted devs using their proprietary silverlight and c# which required a complete rewrite from iOS or Android. Allowing existing apps to bundle their preferred Android runtime is a lot closer to something like containers or flatpak and is a proven way to reduce developer friction. Ironically, such an app running in wasm would be supported indefinitely while Android apps on Android eventually lose support.