Chess and Mathematics both require a large amount of domain specific knowledge and experience to become expert. General intelligence is not enough. Years of study are required, and the vast majority of what is gained is not transferable to any other field.

At a chess tournament several years ago, I found theoretical physicist Edward Witten (https://en.wikipedia.org/wiki/Edward_Witten) playing. He is considered one of the greatest mathematical minds alive today, but as far as adult tournament chess players go, he is only slightly above average.