I don't know if I would believe the results of that video, off hand, given the description, because I'm using an old-style Wraith Spire from an original R5 1600 CPU retail box, on this R5 3600 that was an upgrade to my Gigabyte B450 AORUS PRO WIFI mobo, and it's currently spinning at 2700RPM, with a max listed in HWMonitor as 2732RPM.
So, the old-style Wraith Spire coolers are NOT limited to 2000RPM. Either his was detected wrong, or the mobo detected a new fan installed, and reset the BIOS settings. In my B450 board, I can choose to run the fan RPMs for CPU fan, system fans, etc., based on certain thermal sensors, or just turn them "full on".
He probably just plugged it in, and didn't configure his BIOS? Or his BIOS is buggy? Or AMD shipped out different Wraith Spire (old style) coolers, with different fan motors? (Never heard of that with AMD, but have heard of that with Intel. I prefer the NIDEC Intel stock heatsink fans.)
Edit: What could be happening, is that he left "Smart Fan" enabled in BIOS (probably the default), and the fan RPMs spin up as needed to cool the CPU more, and the copper-cored old-style Wraith Spire is more effective at cooling, thus didn't have to spin up the fan as much. That's my interpretation.