For that comment I was talking about professional D-level simulators for real life flight training.
Simply put, whilst for example, Airbus for example, shares some data with Asobo and Fenix for their performance, they don’t share everything. I would guess in fact that much data is still withheld from home use flight simulators.
That is made up for by us users, and the developers themselves, but ‘adjusting things’ to make it feel correct, or to meet certain performance targets.
The fixed base sim (big real sims) will have much more accurate data, and be required to meet certain performance specifications. They are complex machines, but a large part of their cost will also be coming up with that high-fidelity flight model and meeting the manufacturer’s stringent requirements. Requirements that a home based sim such as MSFS will never have to meet, nor probably even have access to.
So even though MSFS may have 1000 surfaces, those surfaces have to absolutely have to be correct to ensure those interactions are correct. Without 100% the manufacturer data, and the requirement to strictly meet their tolerances, home sims can never compete with the big professional flight simulators. But they get closer every iteration!
Another point though that I was trying to make, is that MSFS basic model that all aircraft work with, is a straight wing, conventional (single symmetrical (left/right) main wing in the middle of the aircraft, tailplane at the back) aircraft, where as other simulators may be able to simulate the interaction against the atmosphere in a much more accurate way. Even if they have less interaction points, they may be able to model swept wings for example, or canards as another.