I've got one of the Quad G5 Macs too, sitting right next to it (in fact, I upgraded from the Quad directly to the Talos 2). The Quad is also very quiet in idle

I've got one of the Quad G5 Macs too, sitting right next to it (in fact, I upgraded from the Quad directly to the Talos 2). The Quad is also very quiet in idle, but you have to downclock it in System Preferences to be as silent as the T2 is in normal operation, and even with a well-maintained liquid cooling system the G5's roar at full tilt is loud (it's really loud if it's not). The high speed fans in the T2 are more like a quiet whine than what the G5 generates, let alone the wind tunnel MDD G4 I ran before that. And no LCS! And the G5 is doing that with four cores and four threads, while the Talos II is doing that with sixteen cores and 64 threads. Now, the Quad G5 also came out in 2005, and I got the T2 in 2018. But thirteen years later I'm happy to say that the noise level is absolutely no worse than any other modern workstation on x86_64.