That's very impressive not to say moving.
Also an incredible feat in terms of recording skills - so many different environments, times, ambient noises, etc. edited and mixed with no audible seams. Surely there would also have been a number of slightly different tempos to match, unless the project guys made each artist play to a click? And then there's mixing it to video! Truly a herculean task.
Could we do something similar? I guess we could do a similar audio project if we put our minds to it. We'd need to lock in the foundations first: song, key, tempo, length, common recording format, etc.

John


Songs web site
YouTube Channel
BIAB 2019
Cakewalk by BandLab
Studio One 4