The new issue is bpo-45383.

There's a sprint newt week; I'll probably get to it then.


> But, I am trying to understand the preference for static better.  There is probably something to learn or even important I am missing.

The original motivating use case is not "create types dynamically on demand", but "create types without details of the C structure being compiled into the extension". That is, make it possible for modules to be compatible with several versions of Python.
The spec is designed to be extensible; the type struct is designed to be fast at runtime.


> And I have some plans to make static specs useful in type checking

This is quickly getting out of scope here, but if you're interested, I put down some notes here: https://github.com/encukou/abi3/issues/19