The most competent software engineers (which I referred to as rock stars) don't know how to do everything. It can appear that way to someone unfamiliar with software. The best have a keen self-awareness of their abilities. They understand how much time it would take them to figure something out, and their likely success rate. When they give good estimates and have accurate confidence in their abilities, they create predictability for others around them. That makes them a net sink for stress.
Professional competence is literally the set of the things you can do without needing help. That doesn't mean you never ask for help. It just means there is an expectation that you can accomplish some things on your own. If you need help with everything forever, then you are fundamentally not useful and not coachable (which is worse). When needing help is anticipated and transient, that's a non-event. When your job is mostly things that you are expected to do yourself, but you need help with all of them, that creates stress for your peers and subordinates.
Professional competence is literally the set of the things you can do without needing help. That doesn't mean you never ask for help. It just means there is an expectation that you can accomplish some things on your own. If you need help with everything forever, then you are fundamentally not useful and not coachable (which is worse). When needing help is anticipated and transient, that's a non-event. When your job is mostly things that you are expected to do yourself, but you need help with all of them, that creates stress for your peers and subordinates.