Win98 was the last OS that MS put out that was 'controlled' by basic geeks who just wanted things to work simply. Sadly, it was based on top of an old, rapidly obsoleting technological model that was becoming unworkable because the internal framework was not really capable of assimilating new concepts easily, without breaking the frame work - also it was only really 'single user' unlike the 'generic multiple user' concept of things like UNIX and its descendants, as well as 'mainframes'. Also newer things like USB were becoming harder to fit in the old framework...

Sadly it had to be rewritten to fix the almost insoluble coding problems coming forward. Sadly an understandable decision for very good reasons was made to try and have a degree of 'backwards compatibility' - no one wants to totally trash an old loyal customer base ....

Sadly, also, at this time the 'engineers & hackers' were displaced by the 'marketers and bean counters' - and it all went down hill from there ....