Earlier quoted context omitted.
Anyone can build and release a compatible browser whereas one would be stuck with Internet Explorer (and no compatible browser) if something were only to work on IE. As it stands, Chromium exists.
How is it any better that something can run on a bunch of slightly different versions of Chromium, but no other browsers built from a different base?
Don't want Google's services in your browser? Download Chromium or the dozens of other browsers forked from that codebase.
With something being limited to working in IE, THERE IS NOTHING ELSE, binary or otherwise.