Last I checked a smallish kernel + uclibc/busybox with most applets (an httpd is in that list) is around 8MB or so. Even glibc only adds 2MB or so more if you throw out the locale stuff. Windows is just a different world.
And BaseFS sounds like VFS, the virtual filesystem layer in Linux also - you'd think it was the most novel idea to abstract away common functionality to a shared core, this design pattern is as old as the hills. These pieces of news carry next to no information, it's pointless that this got onto the front page of HN.
I have no idea why they came to these conclusions.
From the article, a "smallish kernel + xyz" is hard to compare with what exactly is in "MinWin". I suspect the fact that http://www.c64web.com runs on an unmodified Commodore 64 blows your "smallish kernel" out of the water.
My point? You can make assumptions, but you need to know fully what your kernel and other bits include.
The c64web site runs on Contiki OS, which will actually work on less capable hardware. It's pretty impressive, really. I would be tempted to say that it doesn't really compare to MinWin or Linux, but I'm still busy being amazed by it.
I really don't know what you mean by Windows having greater hardware support, I suppose for certain definitions of "windows" and "support" that could be true. Maybe if you count all versions of windows, and restrict your hardware to common CPU archs, and count drivers that aren't built into the kernel. Honestly I have no idea how you'd come up with numbers either way, but my impression was that Linux can be made to run on pretty much any general-purpose CPU. Perhaps you'll provide some data on the matter.
To be honest, windows just pretty much works these days.
20MiB is impressive.
It's almost unfortunate that the term ever leaked out.
Claiming doing something useful with a 20 megabyte kernel is extraordinary is, itself, extraordinary naive.