FBX stands for FilmBox as an extension and was a software application being developed by a company called Kayadra and later renamed MotionBuilder.
MotionBuilder was repackaged as an animation solution for studios needing a front end solution for the ever growing motion capture hardware devices that was hitting the market and to make DCC requirements easier as to different 3D platforms made their native FBX API open licensed.
That’s to say that FBX is a native format and not a import/export format where there really is no “controlled” specification that would cover all the requirements of moving digitally created from one edit environment to another.
At some point Alias, the developers of Maya, bought Kayadra, including MotionBuilder and the HIK technology which in turn Alias was bought by Autodesk not to long afterwards.
The fear at the time was Autodesk would close source the licensing of FBX so the Khronos Group, and it’s partners, started developing the Collada format as to the needs of having a freely available format to fill the expected gap.
As it turned out Autodesk decided to continue to open license the API and continues to support the format as a native format for MotionBuilder and continue to release updates as part of the improvements made to their own product line. Since there is no longer a pressing need for a true DDC wrapper Khronos no longer develops Collada as to improvements to DCC requirements
Facts of the matter is it does work as one would expect from any native format for the purpose of saving and loading data that is native to MotionBuilder so it’s up to the software developer to properly parse the data.
The fact that some have issues with it is nothing new but most arguments against it seems to come from those who think they have a better solution from the many available. In the mean time Epic does continue to update their FBX import and I was impressed when opacity maps just started working.