The M20 is not dead. That is for sure. We have a very large update in the pipeline involving new FMOD sounds, new 3D model, and new textures, and an updated flight model. This update will be free for all existing customers.
The updating for this plane is tricky as it requires a lot of different elements to line up to release the update (being three different variants), hence why it is taking quite a bit of time.
The biggest areas that need (and will get) improvement are, for transparency:
3D Model/textures: It looks like the screenshots, it needs improvement (and will get it )
FMOD: Has some weird glitches and issues. This is going to be fixed in the very short term.
Flight model: Nothing too major, just calibrations are needed to adjust for 11.40 and 11.50.
We are working as hard as we can, both on this update and our other projects. Hopefully this gives you a good idea of what status the M20 currently is in (and where we are planning for it to go!)