Too simplistic Bulto..
You seem to be forgetting the engine rule..six per year.
How many pitlane starts would Ducati have to endure because their engine WAS the frame, like the one they had last year because the engine cases needed a make over for the Aluminium spider monocoque, until they hit upon the solution?
You're assuming this new frame/swingarm package of upgrades is the finished article. That they have the right numbers.
Simply put, this year, engines #5 & 6 have new casings that allow more adjustment and that's with them using a beam frame.
There is no reason the geometry can't be transferred to a new monocoque CF design but..that would be no guarantee of success. The example you give of VR saying there was no difference in the first frames was because the geometry was inherently wrong. If it's wrong it's wrong so it doesn't matter what it's made out of.
If they built a CF bike with the right geometry, maybe then you'd see the real shortcomings of Preziosi's design in carbon.
It's no coincidence that every bike that races at world level runs a beam frame.
If this bike does improve because of the new geometry and getting numbers back into the ballpark, why would you want to go back to the rigid, fixed old monocoque that has limited adjustability?
Part of the reason Ducati haven't been successful, even with Stoner, is because the bike worked good some places and not others. You may need that adjustability to fine tune the chassis for different tracks.