Any time you change the length or the tension in a string, you'll change the pitch. The "wrong" method in the video involves releasing the contact point, letting the finger "float." This is grossly wrong whether or not you're trying to get a vibrato, since you lose an incredible amount of sonority and risk having high harmonics show up.
There's no reason to name this anything other than "one of a dozen wrong ways to produce a clean sound."

I'll note in passing that electric guitarists often bend notes by applying transverse force to the string, but again not releasing the pressure. I believe this is largely because the existence of frets makes a longitudinal vibratro just about impossible. (and then there's a whammy bar :-) ).

Any time you change the length or the tension in a string, you'll change the pitch. The "wrong" method in the video involves releasing the contact point, letting the finger "float." This is grossly wrong whether or not you're trying to get a vibrato, since you lose an incredible amount of sonority and risk having high harmonics show up.
There's no reason to name this anything other than "one of a dozen wrong ways to produce a clean sound."

I'll note in passing that electric guitarists often bend notes by applying transverse force to the string, but again not releasing the pressure. I believe this is largely because the existence of frets makes a longitudinal vibratro rather difficult. (and then there's a whammy bar :-) ).