To address this line, a correct DM for a trainer shows if you've done something wrong. Pranged one in on a hard landing. Clipped a wing in formation. Its the complete package, not just a partial.
For many, the current state is ok. Others want the full capability. Nav via ADF is rather an important feature, along with a Kneeboard for vis Nav.
If ED said this was placed on sale, AS-IS, then maybe people wouldn't expect more than what it is now. But it was sold as EA meaning it was only partially completed.