AFAIK that's simply a fantasy promoted in certain corners of the internet (like the ironically-named r/EnlightenedCentrism). It's not supported by any actual quantitative evidence at all, nor am I aware of any credence given to it in academia. It's essentially made-up. There is no political scientist I'm aware of who takes it seriously.
To my knowledge, it's nothing more than a talking point invented by progressives to try to convince other progressives not to be pulled to the center.