I don’t remember plug n play capability in Win 98. At the time I couldn’t figure out why it was so hard to do.
It was new stuff, especially to Microsoft, and they hadn't figured it out yet. Apple had it figured out better in 1998, but it was still not really good until OS X.
PnP is difficult if your underlying operating system is a hodgepodge of stuff thrown together on top of MS-DOS during a period of 15 years without a good technical design or plan.
Windows NT was a great step forward, and WinXP and Win7 were a huge improvement over Win95/98.
We won't mention WinME or Vista or Win8 because I just ate and I don't need to taste it again.