Transform object null to null value

This is a feature request, not a bug report.

I think this kind of change is out-of-scope for this module because the scope of this module is automatic inclusion of relationship data. Returning null instead of returning data:null is additional processing that may be unexpected and lead to an unwanted change.

This is not a final decision; I am willing to be persuaded by argument.

If this feature is implemented, it definitely needs to be opt-in (off by default so that backwards compatibility is maintained) by a config option.

An alternative is to use the JSON:API Links → module to remove the links.