[yabadabadoes]

The question is really how common each base group is and then how many single field experts each accounts for..

I.e. on one extreme every Expert is a jack of all trades that hasn't reached acknowledgement in more fields. A little absurd, but not as absurd as the other extreme: that all jack of all trades that reach expertise in a field simultaneously get acknowledgement in enough fields to be a Polymath.

The only evidence I see in the article towards that question is the analysis of arts hobbies in Nobel prize winners vs average scientists.