About read-only fields in the macro API

The API documentation for macros says "There are no read-only fields".
When I tried to create a macro with the Create API including all the fields actually described in the document, no error occurred, but some fields were automatically rewritten.
Specifically, id, url, created_at, updated_at, and position.

Why are these values not read-only? Is it possible to overwrite under certain conditions?

In particular, `updated_at` should normally be read-only and I don't think there is any reason to overwrite it.

Please let me know if there is a clear reason or a plan to fix these.