I do not completely agree with what you are saying (I think that in the majority of the cases layers from other CAD programs correspond 1:1 to classes in VW), but in a way it is not important what my personal opinion is. The problem is that importing and exporting back and forth does not reliably work between apps from different software manufacturers although they say they embrace the same standard.
Also the results vary between
- initiating a file in VW, importing in app X, export from app X, importing back into VW
- initiating a file in app X, importing in VW, exporting from VW, importing back into app X
- throwing an app Y in the mix somewhere
- using fixtures from the Spotlight library or those that are not in the GLTF library.
Are there still regular meetings between all of you in the consortium? Please keep talking to each other. We all benefit!