Yes, the weird nerd is rarely a good people manager. As useful as they might be as an individual contributor when property channeled, they can easily be a -10x contributor when you put them in charge of people.
I disagree. A "weird nerd" is much better in leadership than a socially adept careerist to parachutes in to get a bump on their resume. To build good products you need to care. A "weird nerd" is more likely to care.
It would help your point to separate design leadership from supervisory management. You do not want weird nerds in charge of personnel decisions beyond "Yes, we get along" and "No, we don't"; you do want them in decision-making roles about the product.
care, yes but caring about the right things in product is a process of discipline and organizational/ market knowledge. Its not hard to imagine pursuing the most interesting qualities at the cost of core functionality. (hypothetical - such as insisting that the buttons on my cable box have the touch of a mechanical keyboard)
edit: to be fair, it is extremely necessary to have both voices at the table challenging one another
