But the question is a question of probability and information divergence. If 0.0001% of the population was Montessori educated, but 1% of famous people were (whatever your definition of "famous" is), then it is greatly informative. If 0.0001% of famous people are, then it is not informative.

And note that even if informative, it might not be a causal relationship - it could be that the "causal" relationship is "parents who are open to alternative education systems", or "parents who can afford alternative education systems and are willing to", and the Montessori link is incidental. I do not know and I don't think anyone really does.

Regardless, I find those educational principles much more logical than the traditional ones, and would thus prefer them if given the chance.