Because one is an intellectual activity, the other is not. You cannot expect the 60+ year old coach to run and train with the team members. But you can as a CTO

Because one is an intellectual activity, the other is not. You cannot expect the 60+ year old coach to run and train with the team members. But you can as a CTO try out technology, open the terminal, run a docker container to see the technology. Otherwise you are too far away from the things you try to orchestrate. Here the analogy of a master chef comes to mind. She doesn't have to work with her sous-chefs, but it helps to be able to still master the knife, make sushi or make a Crème brûlée, or even an omelette. All while mostly focusing on the big picture.