I did some more digging to find out that the infamous BSOD demo with Bill Gates on stage was meant to show off plug and play on Windows 98. It was caused by a USB scanner.

This happened 4 months before the release date of the first iMac.

https://youtube.com/watch?v=IW7Rqwwth84

Yeah, I mean, I don't disagree with any of this, I just don't think any vendor in the PC world was prepared to rip the PS/2 and serial ports off their motherboards, and tell all the peripheral manufacturers to go take a hike