But you're not removing complexity, just moving it into the wasm-based runtime, and in the process it removes the power that comes with building the browser, which is shaping how the user sees and interacts with websites.
If every website is a blob of code that you have to execute as a black box, what's the point of writing your own browser? It'll just be a slower copy of every other, since all the potential for making it different has been taken away.
A very insightful comment
Browsers are becoming out of control behemoths.
I am currently developing a new kind of operating system using nothing but web technologies (ie, it is technically a single-page web app). It might not be the same kind of legacy hardware-centric operating system that most techies fret over, as I am just interested in "userland" ideas (ie, what new kinds of applications can we build, using what new kinds of higher-order abstractions). IMO, the kinds of research programs you are thinking of are really, practically speaking, solved problems.
Also, my OS is compatible with POSIX, as it is the first (that I know of) Javascript implementation of IEEE Std. 1003.1 (Shell Command Language).
The project is called "Linux on the Web" :
~or~
- https://linuxontheweb.appspot.com
As individual developers, we really need to start thinking of web browsers as the hardware layer, virtualized as it may be. Just as the scripting languages of the early 90's allowed us all to start thinking at higher levels at the language layer, modern web browsers allow us to start thinking at higher levels at the OS layer.
If we ever come to the point where all you need to develop a web browser is a wasm vm, don't you find exciting how much simpler a web browser would become? At the moment it is one of the most complex pieces of software out there. It is so hard to build a modern web browser from scratch nowadays that doing so as a hobby would take a lifetime. This takes the power away from individual developers, since it's not very realistic to build a new browser unless you are a big corporation with money to spare.
This situation also poses a big problem for the development of new operating systems. If your shiny, awesome, new research open source OS does not have a modern web browser, it will never reach wide adoption and thus never atract enough developers to build critical mass. The alternative is to make your OS compatible with POSIX and thus reuse the work of others so that you can build existing web browsers. But then you are most likely bound to become just another unix/linux alike, thus hindering innovation.