So while the different variants have different wing surfaces there is no denying that the Air Force and Navy versions would've been designed differently if the airframe didn't have to fit a lift fan in it.
So then you're back to the fundamental question of why even bother. Parts commonality is 1/4th of what it was supposed to be. Costs are nowhere near what they were originally billed as, even with the most optimistic estimates.
Really the only virtue of the JSF approach was that it made the program too big to fail.
The size of the aircraft is driven by the need to carry large amounts of internal fuel and all internal stores, not the need for a lift fan for the B model. This allows all three models to operate with a reduced cross section for an expanded set of missions, which is the purpose of the aircraft.
Parts commonality is essentially non existent except for the engine and parts of the avionics -- that does make a difference and is a cost savings, but it's not the issue you make it out to be.
Costs are better than they were sold as, and their availability rates are better than they were sold as, and their accident rate is so low as to be non existent. It's a phenomenal aircraft and a capability that's going to completely change the balance of power in some regions of the world.