I don’t see how you got “you can’t use a server OS for regular work” out of that; the features that induce users to purchase Intel-compatible PC operating systems don’t necessarily bear any relation to those used for “regular work.” They could be things like hardware support and game compatibility. Surely playing games is not “regular work” for most people.
If you think that a typical consumer couldn’t use NT 4 Server (or Win2K Server) as a replacement for Windows 9x, well, that’s up to you, but I strongly disagree. The FoF suggests that to be the case, but I don’t believe it’s correct.