That's not really fair to MS since all the web frameworks which were born in that era (Adobe's AIR, JavaFX as a web tech, etc.) died because IE died. And also because Apple killed off browser plugins since they didn't work on the iPhone. Chrome and Firefox took over and there was no longer a need to use browser plugins for SPA's. HTML, CSS and Javascript finally got the features needed to create a proper SPA.
While JavaFX did live on outside of the browser both Adobe RIA and Silverlight were far worse positioned for life outside of the browser (even though both claimed to be usable outside of the browser). Simply because JavaFX was meant to replace Java Swing.