Every 10x engineer I've known has carried entire teams of normal engineers. ymmv but I've seen probably 5 instances of this and 0 instances of teams of normal engineers being super productive.
I’ve seen the opposite: plenty of examples of very productive teams with really no standout “10x engineer”, and several examples of unproductive teams purely due to poor team decision making. IME, productivity is a measure of past investment, not current skill.
What are the details of this? Any engineer that built most of the stuff is not a 10x engineer. It's someone that really knows their way around their own house.