Talented vocalist. Very!
Not a deeply educated musicologist, so the earlier eras weren't truly captured, nor were the subtle evolutions of harmonic structure clearly delineated.
Bach opened the floodgates, so to speak, with his brilliant use of the tritone.
But an accapella arrangement will tend to have a 'sameness' to the sound no matter what era it purports to be from. So the differences in each era are equalized, and the addition of rhythm is the main variance.
But this guy has a simply gorgeous voice, beautiful execution, crystal clear intonation.
Change the word "music" for "clothes" and it's the same old argument. Things change, we change in accordance to whatever era of time in which we happen to live. That is the process of life. Our music is going to reflect that, our dress is going to reflect that, our speech is going to reflect that, our tools and way of life are going to reflect that...etc.