They were fake long file names though. At the actual dos layer they were 8.3. And the plug and play was terrrrible. I always turned it off. Ugh the plug and play modems/soundcards were trash.

You're not wrong, but PnP including the configuration basis for PCI which still sits at the config space layer of the latest and greatest PCIe. That's the piece I find so significant. I work with GPUs that mostly communicate over a proprietary C2C connection, but how does the OS find them? PCI enumeration.