I thought it an interesting comparison.
Not really pro but just as far from incompetent.

Missing the point that a stereo pair was contrasted with a single or that stereo mixed matches were used to demonstrate the DIFFERENCE or lack thereof in capturing an acoustic guitar is a) par for the course and b) more telling of the commentator than the presenter.

Capsule distances may have, and by the sounds of it were, varied to accommodate difference in level &/or what suits the mic...it would be less than transparent to crank the preamp to compensate.

The comparison worked..there were "darker", "thinner", "rounder" and "harsher" captures.

I have a few of the mic models in the demo.
As with many folk I have a range of mics collected over time and "upgraded" as needs and technique required. From a few Sony Electrets, Apple IMac accessory mics, boundary, no names, Behringer to "nicer" things but each has a place and a purpose.
A producer introduced me to the Sony ECM-19B electret condenser microphone...one of those little 70s types that requires a AA battery to be inserted in a body that's not much bigger than it. It's a cheap thing with a bit of self noise but minor tilts and angle changes work wonders with different acoustic instruments and it's really quite nice on cello.
In the end it's what you have and what you can do with it.

Cheers
rayc
"What's so funny about peace, love & understanding?" - N.Lowe