Smart and creative peope can grasp a lot of things but not everything is pure thought. Experience and experimentation time is required and there are only 24 hours in a day. Also the ds field has a lot of young people that did not have that much time or opportunity yet.

My N is a few hundred, not all my personal hires. I have visibility because now I do project management office duties (build sub teams per project), lead most of the interviews on the ds side, internal technical consulting duties. Ten you mentioned is my target number for hires previous and next week approx.

My claim is based on experience from the academic and the consulting space for global corp (which included consulting for other corps to build their ds teams, rarely though). I hope my claim appears logical and is useful.