News Developer ports Windows NT to Power Macintosh systems — firmware and boot loader now available

IMO, Linux would be a better use for them. You can actually buy much more recent POWER (desktop) machines, for running Linux.

Back in 2018, they were the first to support PCIe 4.0. Nowadays, they're getting a bit long in the tooth.

Anyway, one thing I wonder about WinNT on PPC is whether it ran in Big Endian or Little Endian mode. I'm pretty sure PowerPC was bi-endian, enabling it to support either. These days, most people running Linux on POWER seem to use Little Endian. As that matches Intel, you probably run into much fewer issues, that way.