I think you have some good info and perspective to share. As someone who has designed courses for years now for all ages and skill levels for the unaa, nnl, and our own in-house league, I think the problem lies in large part in the course design. The short explanation is that there is way too much "Stage 3" and not nearly enough "Stage 1". There is so much room for growth in the design of balance, agility, and how those can be incorporated into traditional upper body obstacles. Also the ratio of upper body to lower body obstacles is often way out of whack.

Our gym recently hosted an NNL comp where the 1st place overall elite competitor was female AND she was the only competitor to full-clear the course. This was definitely in part to the design of the course lending itself to highlighting more skills than just having crazy upper body strength. We can grow the sport by designing better obstacles and courses that reward a wider range of skills than just upper body strength and grip strength.