gentlegreen
I hummus, therefore I am ...
I once had the great misfortune to be on the interview panel for my assistant and was conned by an idiot with two degrees - one in physics, the other in maths - thence commenced several awful years of working with a synthesis of Frank Burns of MASH and Homer Simpson.He has a degree in physics (along with one in economics) which makes me think he can probably discuss stuff with the specialist engineers at a decent level, and therefore be involved with much of the engineering but only at a high level like you say. People with highly specialised aerodynamics, fuel/propulsion, material science type phds/masters/experience will be doing the actual engineering/design work surely.
And if you look at Thunderf00t's debunking of multiple insanely stupid multi-million dollar projects, (including Musk's) there are "scientists" galore involved.