By RDF did you mean RDF/XML specifically? JSON-LD is still RDF, it's just serialized differently, which is fine, I like RDF, but OP may have more specific concerns than the syntax.
Well, it also contains usable ordered lists. Which is not a small addition to rdf (it defines interop with rdf’s version of ordered lists, but the one in json-ld is array based with random access patterns and a .length while the pure rdf version is purely linked list based without any guarantees about having only one link)
The specific concern is that it's a 100th attempt at creating metadata for everything in the world. You can't create a non-ambiguous comprehensive catalog of the world.
