I would like to suggest to move X3D IO add-on to community support.
It is currently partially working in 2.8x, but would need some work if we wanted to keep it in official support status.
There are several reasons for that:
- Current add-on code has some serious issues (especially import one regarding parsing, its faked-XML-like support is a joke, see T49799 iirc).
- It needs a full rewrite of its material support to handle basic Principled-based nodal shader.
- In general that format is more of a legacy thing I think. So investing BI dev time in it does not look very wise.