If you watched the vid, it is clear that all engines are not born equal regarding a break-in period.
There are engines that are run on a bench, most are not.
Running all engines on a bench for the equivalent of 500/1000 miles is not achievable and doesn't happen.
Though, cylinder walls and piston ring technology have advanced in a major way as power loads have increased on virtually all engines.
The engines I refurbished to as new, were all street run-in, good insurance for longevity or performance use.......