I think this is a good idea because it reduce the effort needed to input thing into fields to achieve: Suggestion for all Plugin developers about field name: Let's use Ontology to maintain Interoperability
Natural language + markup make it easy to input tuples. And to make the plugin developers easier to use these tuples, we still need them to be in the fields. (imagine you are a plugin developer, how will you use data?)
Maybe there can be a plugin to auto-extract these sentences into JSON-LD and put them into fields.