First, though I must agree with you that Win98 certainly does not "just work," it does offer a "stable" platform in the sense that you know what its problems are, and you can modify your behaviour to work around those problems. This is not an endorsement for using Win98; I do not use it, and I don't tell anyone else to use it. However, there are several people I know who do use it without my blessing, and they use it for the simple reason that they prefer the devil they know to the horrendous Microsoft concept of "change is our most important feature."
Along this line, your statement about Windows people being the only ones who want to hang on to their applications for decades if utter rubbish. I myself firmly cling to many such applications I have been using since 1995 on my [Linux] box. There is tremendous benefit of not having to relearn the use of various applications each time a company wants to make a little more money.