Yes, that's great for videos, but many audio players don't support matroska containers. Putting the opus audio in an ogg container seems to be most effective to get a playable file for most people, so that's my default suggestion.
Isn’t opus the default companion for both H.265 and AV1 in an MP4 container?
So why wouldn’t opus audio only in an MP4 container be playable everywhere those things are as well?
I really think we need to stop overloading the .MP4 file extension and standardize “.av1opusmp4” or “.h265opusmp4” or similar even though it is still an MP4 container. Even .webm is now overloaded with two codec generations.
We don’t get a “codecs” HTML attribute in a file system (at least not portably).
