Here's a Titanium PowerBook G4 ad that says "Sends other Unix boxes to /dev/null": https://www.reddit.com/r/vintageunix/comments/b4kojo/sends_o...
Here's a snapshot of the software solutions page for the aluminum PowerBook G4 from November 2004, proudly touting Unix and even X11:
https://web.archive.org/web/20041126011836/http://www.apple....
Some quotes from the Power Mac G5 page (https://web.archive.org/web/20041126015955/http://www.apple....) from the same era:
"With the Power Mac G5, a researcher can now run both productivity applications and high-performance UNIX applications on a single system. Mac OS X Panther includes 64-bit optimized system math, vector and image libraries that take maximum advantage of the 64-bit G5 processor."
There was also a cluster in Virginia made of Power Mac G5s, which Apple also touted.