Might be the exception to the rule, but bill gates, extremely technically proficient and an amazing leader. I've read multiple accounts of staff who worked with him saying it was astonishing the level of detail he knew about their projects.
Could probably add Eric Schmidt to that list.
Whatever problems Google has, Sundar's technical background has nothing to do with it. Which either way with an engineering and science background and 20 years at the company is in itself more than decent.