Reading the proposal for encoding w/ inheritance I see this comment:
If a shared container is desired, it is still possible to call `super.encode(to: encoder)` and
`super.init(from: decoder)`, but we recommend the safer containerized option.
However, this seems to cause EXC_BAD_ACCESS when attempting to do so.
I've attached a playground that exhibits this issue with a contrived example.
Not sure if this is Foundation or Standard Library related.