For those who played competitive chess at young age...

Yes, I used to be good at both. However, I stopped playing chess when going to the university. It was a pity, as I was selected to play the national junior championship.

OK, I get it....People who do A are usually good at B.....But, in life, there is also C to Z......

Chess and basketball, or having girlfriends, or having friends, or being happy, or being social, or drugs, or a good public speaker, or........it can go on and on and on.

I'm sure people good at the piano are good at ........

If you had a kid and he was playing chess all day while kids played in the park......well, i don't know.

chess team and math team........versus football and track team...... as a kid, there are different metrics. being liked is definitely one of them.

There are many other things in life. The original poster asked for anecdotal evidence of a correlation. That does not mean it is in any way desirable or recommended. One can ask if all the energy put into chess would not be more useful or rewarding if put into some other pursuit. Also: if you are good at chess and mathematics, is it then more worthwile to develop other areas where you are weak or if it is better to do what you are good at?
There are also other correlations like between chess and mental illness, read "The Psychology of the Chess Player" by psychiatrist and top grandmaster Reuben Fine.
There is also a correlation between chess and criminality. Once a big match was organised between a university and a jailhouse. The jailhouse won.

I do not care about my PSLE.