@steve I merely observe the huge struggle with LD. Where experts "get it" and non-experts hate it. Where there's a ton of discussion on how it should be used correctly. How its so very easy to use some LD flexibility that makes things hard for JSON-only folks.
AP on protocol level is about msg exchange, mostly Activity{Object}. Yes, technically all linked data, but it may also be usable semantic graphs once it enters your own data store, and be closed-world concrete msg definitions until then.