During the entire time that Microsoft held this so-called monopoly---which was at most a monopoly on the desktop, not the servers or networks that most people think of as comprising "the internet"---Linux and other unix-like OSes continually made progress and now power the vast majority of the systems that provide the internet and indeed the devices we use to access it (tablets and phones).

I'm not persuaded that Microsoft substantially held back the internet. IE of a decade ago was not a great browser by today's standards, but the hardware of the time could not have really supported the javascript-heavy apps that we take for granted today. I occasionally use gmail and google maps on a G4 powerbook with a "modern" browser (TenFourFox), and it's pretty painful. It almost feels like being back on a 48K dial-up ISP service. And let's not forget that Microsoft invented (or at least had the first browser support for) the scriptable XMLHttpRequest, the foundation for almost all of the asynchronous web apps that we use today. In fact way back in IE 5 (with the MSXML ActiveX plugin) you could build rich, responsive interfaces and asynchronous interaction using XML, XSLT, and scripting YEARS before you could do it in any other browser.