From a synth-geek perspective, I might rename the term “Vibrato” to “Frequency Modulation” or “FM", because vibrato (usually a guitar or vocal modulation ‘effect’) never gets to the speeds that this particular modulator does, usually no faster than 2 - 10 Hz = pretty slow. If it did, we would have some VERY bizarre vocal/string/guitar pedal sounds!
The same goes for “Tremolo” - a quick rename to “Amplitude Modulation” or “AM” - again due to actual speeds being beyond human capability.
From an email conversation: