The frame-rate dips he saw were very much likely due to shader caching, IMO. Did a fresh install on my 3070/3700X rig after watching NXG's vid, waited for it to complete optimizing shaders, and then jumped into the gameplay at a very conservative 1440p, DF optimized (med-high) settings with a 60fps cap. The result?
Well, see it for yourself:
Oh, before that, here's a quick screenshot of the HW resource monitor to show idle CPU/RAM/GPU util. before booting up the game (0 background apps running except for OS-related tasks):
Here:
It stutters so much initially on the first run to the point it feels unplayable for a moment, but after a while, the perf gets stable when you go into the same location where it stuttered heavily before, there are still one-off stutters here and there but nothing major. So this has got to be shader caching related problem and likely what we see in NX's vid as well, nothing to do with his HW of choice, IMO.
Mind you, the CPU I'm using is slightly faster than PS5's and what Michael has used in his vid and the GPU is also quite a bit more powerful + I'm putting a lot less rendering load on it, yet I see some nasty hitches, frametime spikes, something that not even PS4 suffers from. The PC version definitely has issues and isn't as stable as the console versions as he concluded at the end.
Here's HZD's CPU cores utilization if anyone's curious: