Actually that is not true. From the time that NT was under development, the goal was to drop the 16/32-bit hybrid version of Windows within a short period of time. Microsoft truly believed that people would move to NT 4.0 because it was better than Windows 95/98. They thought that the lack of movement was perception which was why NT 5.0 was renamed 2000 (basically to get people to move to it because it followed in line with the year naming pattern that 95/98 had set. When that didn't work they ended the line with the release of ME and moved everyone over to XP (NT 5.1). They terminated support for Windows 95 last year, and they are terminating support for Windows 98 within the next year. Microsoft (and Gates) got tired of waiting for people to realize that the NT line was a better operating system than the DOS-based Windows, and they forced the issue. They are moving all their customers to NT.
Get your facts right. Microsoft has wanted to move people to a pure 32-bit OS for years, but they never wanted to do so with NT 4.0. NT 4.0 was meant strictly as a corporate workstation, and having worked with it, I can tell you it was a pure nightmare to set up in terms of driver installation and such. That was the first major strike against NT 4.0 as a consumer OS. The other major strike was that driver support was nowhere near as broad as Win95 at the time, so it was extremely unfriendly in terms of compatibility for stuff like joysticks and other consumer gear. And NT 4.0 couldn't run DOS apps like games, which directly accessed the system hardware themselves. That violated NT's security model where the kernel is the traffic cop handling all calls to the hardware, not the applications.
With Windows 2000, Microsoft managed to vastly improve installation and management. Plug and Play and all that other stuff had been successfully integrated into the NT kernel. The driver database was there. Still, it wasn't quite ready for consumer prime time because of trouble with certain Win9x aplications, mainly games. That's why Windows 2000 Professional was geared toward corporate workstations, and an interim version of Win9x (the deservedly much-hated Windows Me was developed).
With WindowsXP, Microsoft has finally completed the migration to a pure 32-bit OS for both consumers and professionals. They incoporated better legacy support for apps, even throwing in a Compatibility Mode function that allows the OS to fool the application that it's running in Win9x. Driver support is massive. Application support is massive. Stability and Reliability are there. All future Microsoft OS' will be built on the XP/NT technology. There will no longer be two seperate OS lines built on DOS and NT, they will all share the same NT codebase from this point out. That is what Microsoft has been wanting to do since 1994, and they finally got there. And now they're at this point, they're actively pushing their consumer customers to upgrade to XP for the same reason Apple is pushing its customers to upgrade to Jaguar; XP is a better OS in terms of security, reliability, stability, speed, and multimedia. But unlike Apple, MS still continues to support its older OS'.
While it's true that this doesn't include Win95, it's also true that Microsoft has publicly stated (and this is also on their site) that six years is the lifetime they'll actively support an OS version. MS still supports Win98 and WinMe, but Win95 and DOS are both over six years old and now are history. Fair enough, six years is ancient history in computing.
How old is OS 9, and how quickly did Apple kill it's support of it? I bet you it's been far less than 6 years.