This demonstrates that old adage, you can prove anything with statsitics.
It confirms that cars lose a percentage of their value over time. e.g. two cars costing £130k and £61k new, that depreciate by say 40% over the first 3 years will lose £52k and £24k respectively. i.e. 40% of a £130k car is more that 40% of a £61k car. So, if you want to lose less money, buy the lowest price car to begin with. Seemples as the meerkats would say.
I'm sure if we were to look at Glass's Guide or CAP Black Book for F type depreciation rates, we would find very similar annual percentage drops across the engine sizes as they age.
The video also highlights significant depreciation for the SVR, when it has relatively high mileage/km. However, the sample size for this study only looked at circa 30 SVR's that were for sale in total. So, statistically this is maybe only extrapolating one car with high miles/km and drawing the general conclusion for that car to be the norm.
The statistical problem with the 400 and SVR is going to be the that sample sizes are always going to be small given the 600 and 2500 cars produced globally out of nearly 80,000 F types. i.e. one rough car is going to distort the results. There's no logical reason for them not to follow the broader trend, until say they become classics in 40 years time.