I need to reiterate what I said in a previous post.
PMDG aircraft use a proprietary nav data format, which is found in every product they have sold for the last 20 years on all platforms: FSX, P3D and now, MSFS.
The nav data is the heart and soul of the FMS. Almost every internal function of the FMS depends on it, and PMDG FMS units are specifically coded to work with their own format.
It’s not that they couldn’t change to using MSFS native data, but doing so wouid involve many months of work. It would involve completely re-coding much of the FMS internal logic. If they had decided to do that from the very beginning, the initial release of the 737 for MSFS would have probably been delayed by at least a year. Instead, they used the tried and tested database format they had been using for two decades.
It wouid be like converting a gasoline powered automobile to run on diesel. You can’t do that by simply slapping a “diesel” placard on the fuel cap, It would require replacing the engine, fuel tank and pumps, engine computer and the exhaust system. It is by no means a simple or trivial exercise. Changing a pre-existing well-tested proprietary nav data format in a sim aircraft to something else would be similarly difficult.
The default MSFS nav data is improved now, but when MSFS first released that was not the case. It was very poor quality in the US, and that is squarely the fault of NavBlue. Their real nav data for real aircraft is lacking in the US in many ways. Missing data (especially for smaller airports) and worse, obsolete data. When MSFS first released, there were several waypoints in the vicinity of my home airport (KELM) that were deleted by the FAA from the national airspace system over 10 years ago, and yet were still present in NavBlue’s MSFS database.
They are a very Euro-centric company, and their nav data for Europe and Asia is apparently quite good, and is “OK” for major US airports, but not smaller ones.
With only a couple of exceptions, no US airline uses NavBlue nav data - they all use either Jeppesen or Lufthansa data. The situation in Europe is different, where NavBlue has more market penetration.
I don’t make that statement as a simmer. I am the avionics maintenance manager for a large corporate flight department, and am intimately familiar with the strengths and weaknesses of various real-world database providers. My company uses Jeppesen. If I were ever to switch us to NavBlue I would probably be fired.
MS/Asobo recognized the problems with NavBlue data in the US too. About a year and a half ago, around the time Working Title came on board as an official developer for MSFS, the default nav data source for the US no longer comes from NavBlue, they switched to using FAA CIFP data files which are far more accurate and complete. (And are free).
Since that change, the default MSFS nav data is far better than it once was - at least for the US. I don’t think there were (or are) serious issues with the default data elsewhere in the world, though I do believe that the Jeppesen data supplied by Navigraph is still more complete.
The point with PMDG is moot, because they are already in the process of changing the nav data format they have long used, to a new ARINC 424 based solution which will be far better suited to modern RNP RNAV procedures. Because of that upcoming change, there would be even less reason for them to change to using default MSFS data at this late date.
I completely understand that some people may object to paying for Navigraph data (on PC where it is fully supported), when MS provides default nav data for free - (although it is often not updated in a timely fashion - sometimes delayed by many days or even weeks from when the r/w cycle updates).
But, as I have explained above, there would be no business or technical advantage for PMDG to change to using the MSFS default data. Ditto for Aerosoft, Leonardo or Fenix, who have good reasons for using their own proprietary database formats.
The problem on XBox is a Microsoft limitation. No files on XB can be updated though any source other than the Marketplace. Technically, PMDG could update the 737 nav data by updating their XB 737 through the Marketplace, but they legally cannot do that because they do not own the nav data - Navigraph does. Any solution for getting newer nav data in the PMDG 737 on XBox is going to have to come from Navigraph - not PMDG.