Seems reasonable, from what is known about the capacity of speech, although extra cool if there is really some universal number we converge on. Kuyk and Kleijn

Seems reasonable, from what is known about the capacity of speech, although extra cool if there is really some universal number we converge on. Kuyk and Kleijn found the upper bound of the speech channel to be 100 bits per second, in agreement with the lexical rate of about half that in "ON THE INFORMATION RATE OF SPEECH COMMUNICATION" (https://ieeexplore.ieee.org/document/7953233 https://ieeexplore.ieee.org/document/7953233) using an interesting method based on mutual information. Some highlights from the introduction that are relevant: Broadly speaking, two approaches to measuring the information rate of speech exist: the linguistic approach, and the acoustic approach. The linguistic approach describes speech as a sequence of discrete perceptual units such as phonemes, words, or sentences. Taking the average talking speed as 12 phonemes per second [3], and using the English phoneme probabilities tabulated in [4], the lexical information rate is approximately 50 b/s. When the dependencies of the phonemes are accounted for the rate will be decreased further. The lexical information rate does not include information about talker identification, emotional state, and prosody. However, these variables vary relatively slowly in time and contribute little to the overall information rate. As an example, [5] estimated that the total amount of talker-specific information (e.g., age, accent, sex) was of the order of 30 bits