This sounds very unfortunate but what I was expecting, I dont see why we need yet another proprietary format for people to fight over and it just makes things more difficult for those of us who have to write support for X DCC tool.
Open formats that are extensible similar to Pixars USD allow data to be used or dropped as required rather than requiring a strict data structure so that every piece of data conforms and thats why I do like the look of glTF is it does have room for additional data at very low development cost. It means there can be a standard for the core of a format and for those that need more they can still use said convention without having to reinvent the wheel every time.
It seems odd to me Epic chose to go this route since there are quite a few intermediate tools that specialize in format conversions, they even work on commandline for heavily automated pipelines.
Thanks for the information, I feel even better about pursuing this path as I was worried I was doing rework that would end up obsolete fast, it means I keep my competitive advantage in regards to my pipeline