Having said that, no simulator Level D is particularly realistic, stemming, as an oversimplification, from two areas.
(1) The manufacturer's data packages simply do not adequately cover the possible dynamic, what is there for attitudes beyond the certified flight envelope are very rough approximations, if anything is offered at all. One particular manufacturer is now considering withdrawing all but certified data, due potential legal liability.
Point taken re fidelity. It should be remembered that nearly all fatal accidents caused by poor handling in an unusual attitude, happened in IMC or at night. In other words the crews displayed poor basic instrument flying skills and paid the ultimate penalty along with their passengers.
While it is agreed that G forces cannot be simulated in current Level D simulators,
flight instrument indications of an unusual attitude are still valid.
Therefore the basics of unusual attitude recovery on instruments should be taught. For example un-load and using full control wheel roll in the shortest direction to the sky-pointer if inverted. Or roll to the nearest horizon if extremely nose high, to drop the nose.
Perceived legal issues aside, even if a future simulator did have full fidelity with G forces, the basics of recovery on instruments are still the same and that is why unusual attitude recovery practice in a simulator on instruments is needed for a pilot to be deemed proficient. The alternative is to learn from a book at leisure. That's as useless as learning to swim from a book.