codes: Interoperability is not related to symbologies. The ability to scan a particular symbology is a relatively simple piece of an application.
The term interoperability is limited to the concept of indirect encoding. For example, if NeoReader scans a Mobile Tag indirect code, it needs to be able to direct that code to the correct resolution server. For interoperability, you need the various players using indirect encoding to share a registry. This is yet to happen so interoperability does not exist today and there are no efforts by the various US competitors to share their data.
You do not need interoperability for direct codes.