[teilo]

I entirely disagree with your premise that a CTO should know as much about coding as a top developer.

No, a good CTO should have a broad understanding of technology and the development process; understand finance sufficiently to manage the budget of his department; have good communication skills so as to translate the needs of the business to the people who will be implementing the technology to support those needs; and be a good project manager so he is able to properly delegate tasks to those best suited to completing them, and keep his resources accountable.

He should certainly understand code, and perhaps even write code himself. But be able to replace any given person he manages? No. He does not need to be an effective coder. He needs to be an effective manager, and ideally a servant leader.

I speak from experience, as a CTO.