You cant manage project on people skills alone. That just don't work all that well and is likely to lead to crappy product and massive crunch. You cant manage project without at least some technical skills. You don't need to know all details, but you need to know enough about tech to understand general concepts, what is possible, what is risky, what technical debt means, when people lie to you about tech. In order to be good project manager you need both, but you don't need to be super genius in either.

And there are also skills (or attributes) that makes you both better programmer and better manager: being organized, systematic, being responsible, willingness to do also boring tasks, understanding what people say when they talk to you, ability to explain yourself, good memory, etc.