I'm not sure that's an apt comparison. If you were saying that 32-bit PPC is dead, then the answer is probably yes at least in general computing, though there are still lots of 32-bit PowerPC parts in embedded systems. However, 64-bit PowerPC systems have substantially more in common with "big" POWER. The G5, which was clearly positioned as a member of the PowerPC family (PPC970) but descended from the POWER4, would be the classic example.

PowerPC is dead for the larger market but sticks around in specialty markets. Mainly NXP (formerly Freescale):

https://www.nxp.com/products/processors-and-microcontrollers...

Also, the separation kernels that met NSA's highest standards of security initially targeted that for cross-selling into aerospace market. They buy a good chunk of PPC for some reason. Example that was among first certified with data on what was expected:

https://www.ghs.com/products/safety_critical/integrity-do-17...

The Talos II I'm typing this reply on is just my regular workstation. I have a dual-4, which is 32 threads, and it runs Fedora. Most things work just fine and it's a very nice daily driver. I'll probably upgrade it to a dual-8 in the near future for even more parallel goodness.

I also have a Blackbird, which does streaming video in the home theatre and is also a test system. It's a single-4, but it can take an 8-core part if desired.

They are primarily intended for people who need lots of threads for high-end workstation uses (see Phoronix's benchmarks[1]), people who want open computers (whether for security/auditability or ideological reasons), or just people who want something different from the mainstream.

[1] https://www.phoronix.com/scan.php?page=article&item=power9-t...