This belief stems out of ignorance and such jumping to disastrous conclusions by scanty or misdirected research is unfortunate.
In India, the 22 Shruti concept has been known since ancient times.
To opine that our great ancestors who were experts in Mathematics, Astronomy and Music did not know what they was saying, can only be an act of self-delusion.
Because the mathematical basis of these 22 Shrutis was not so far conclusively known, there has been a long drawn debate in India with research workers somehow wanting to somehow resolve, or discard the Shruti system.
Some have even questioned the basis of the number 22 (not knowing Shruti-Nirman-Chakras, and the mathematical and natural evolution of shrutis) and postulated that it could be infinite.
Some workers have even commented that the concept of Shrutis is only theoretical and mathematically insignificant, and that the number of Shrutis can vary from expert to expert, and can be 22, 24, 44, 49, 66 and even infinity ! 22 Shrutis are not variable depending upon one's ignorance.
Firstly, it must be reiterated that 'all' the frequencies sung or played in a concert are 'not' Shrutis ! ! (See Topic 5) Notes sung or played in a concert can be infinite, but they are used as addition only to link or support the underlying framework of '22' Shrutis.
The ancient Pythagorean, Mesopotamian, Just Intonation and Indian; all the ancient musical scales have arisen from basic mathematical principles behind the musical notes.
The 'natural 5 prime numbers' give birth to 22 musical notes, which are demonstrable by playing them at precise mathematical divisions of the length of any vibrating string. Being similar in origin, there have been striking mathematical similarities in the musical notes of the Indian 22 Shrutis and these ancient scales.
Musical note is playable on any string by reversing it's mathematical ratio.
Number is the ultimate language of logic and any principle. 22 Shrutis have substance, are precise, and can therefore be defined by a mathematical number and demonstrated by physical frequency by playing on a string at precise points.
Now, with a clear logic, backed by mathematics, and finally producing audible and appreciable musical demonstration of these notes on the 22-Shruti-Harmonium, 22-Shruti-Metallophone, and the 22-Shruti-Veena, the 22 Shruti concept should be understood clearly and taken seriously.