As I've heard the history, Microsoft tried to use a forward slash for directories in DOS 2.0, but IBM insisted it be a backslash so that it didn't conflict with the parameter switch.

Yes, the (recently released) source code for MS-DOS 2.0 is liberally sprinkled with comments that indicate Microsoft fully intended for the path separator character to be '/' and the command-line option designation character to be '-'.

Microsoft had to design a new API for DOS 2.0, as this was the first version to support hard disk drives and hence required support for subdirectories to organize the filesystem. The API was intentionally designed to mimic Unix. [1]

And it was also intended for devices (such as CON, LPT1, COM1, etc.) to be prefixed with the special directory name 'DEV', as in '/DEV/CON' and '/DEV/LPT1', just to make it feel even more like Unix. [2]

Apparently the idea was that MS-DOS would be Microsoft's single-user operating system running on cheap 8088 machines, and Xenix would be their "enterprise" multi-user operating system running on high-end 80286 systems, and programs could target a single common DOS/Xenis API and could be run on either OS.

[1] https://github.com/microsoft/MS-DOS/blob/master/v2.0/source/...

[2] https://github.com/microsoft/MS-DOS/blob/master/v2.0/source/...

I think you mean Bill \\\\ Gates.

hmm, yes the \\\\ does make a nice Gate icon.