Explorer and Internet Explorer were deeply married, with the ability to set web pages as desktop background, the Explorer of Windows 98 having a "sidebar" that was an HTML page, the ubiquitous help format being compressed HTML pages with index and search, ActiveX giving webpages desktop-application-like powers, JScript being a powerful javascript-compatible automation language for Windows. Windows was full of web technologies in the dot-com era, many bringing web and desktop closer together. This stopped an reversed course in the early 2000s. You could now say that's classic embrace-extend-extinguish, but the collapse of the dot-com bubble explains explains the sudden lack of investment and increasing distance between desktop and web just as well.