hmmm. I think that if users are keeping the json representation in memory and passing it around, that's generally an anti-pattern, right?  I see these traits as convenience functions for one-off things and to patch functionality holes, not as core API. `Dyn____` is our in-memory representation of ABI information, and greedily resolving a `JsonAbi` into a `DynAbi` is the longterm officially-recommended path