Microsoft was signed up to port Windows NT and it looked like you'd be able to run Windows and MacOS (the two most popular desktop operating systems) and possibly some of the other less-popular ones (most of which were m68k-based) on the same hardware.
You left out OS/2, which Lou Gerstner hadn't given up on yet (although the nightmare of the PPC port helped him make up his mind). IBM at this point still had hopes of re-conquering the desktop market, and the CHRP (Common Hardware Reference Platform, aka PPC hardware design) was part of that. Alas, it was not to be. I have booted exactly one machine in my life - a small tower RS/6000 running AIX - that came up and proclaimed itself to be a CHRP machine.
IIRC, either Windows NT 4.0 or Windows 2000 did, in fact, ship with a PowerPC install on the CD, alongside i386, Alpha and MIPS. Whichever it was was also the last of the NT line to support multiple architectures until 64-bit came along.