While I definitely agree that the project is dead before it starts, there are specific cases where Windows x86 software would run on a PPC version of Windows. But that would require said programs to call only on API's and not make any hardware calls.
But as stated, there is no benefit to doing all the work to bring our PPC Macs to Windows NT 4. Even NT 4 x86 wasn't useful as a desktop OS when it was current.
Much desktop software wouldn't run in NT back then. It was best suited for server side software.
Today, essentially every Windows version is stemmed from the NT core. But you're not going to get today's titles to run on NT 4. Just not happening.
I'd love to put my G4 Mini back into daily use. But aside from hobby use or using the titles from back then, it's prime has passed.
Personally, I'm considering MorphOS. But I haven't really convinced myself that I enjoyed Amiga enough to make it a daily use platform either.