You had me at 'actually'.They make a pretty fair conclusion actually. I did pretty much the same tests of aluminium heatsinks 20 years ago when developing high-end hifi amplifiers.
We concluded that black paint was better than raw aluminium but performance was measured best with matt black anodizing as this is a chemical change to the metal surface and not a coating with its less desirable barrier effect. We tested open air convection versus forced air conduction and determined the same conlusion as the video. Of course we went with convection due to the sound intrusion of running fans and combined it into a hybrid setup with large copper interface plates due to its superior thermal properties over aluminium, and the highest surface area of black anodized aluminium fins we could fit into the package.
Take it that you have a polished silver one?#meh
I'm sure there's opposing data points on the web about polished ally ICs if I could be bothered to find it. One youtube video does not maketh the gospel however well produced it appears....
File under: 76% of statistics are made up on the spot.