The kernel is just a bunch of code. What prevents the browsers from implementing all the capabilities of the kernel? Why can't my computer boots into a browser directly and it then figures out how to talk and manage the hardware directly.

The way I see it, OSes of today is simply an implementation detail of the browser. 99% of the world won't even care or notice f Windows 12 is is shipped as a Ubuntu distro with familiar UIs. Heck, not even most developers will I think.

I have this thought when I ponder on the fact that most programming languages of today assumes a virtual machine of one kind or another. But...the OS is already a virtual machine (of the yesteryear I suppose). The only reason we don't have yet another level of virtual machine inside our browsers is that most browsers are almost fully compatible. Even each browsers starts having diverging APIs then its only a matter of time before someone creates an OS on top of browsers.