Saving tags to WAV files are generally not very widely supported. I would recommend that you encode your WAV files to FLAC which is lossless, an open standard, and has full tagging support.
If you must use WAV, then there is a couple of relevant tickets you can vote on and/or follow:
PICARD-41 - Support for tagging WAV files with Broadcast Wave Format
(The tickets.metabrainz one is specific to the MusicBrainz Picard program, the GitHub ones are for the tagging library, mutagen, Picard is using.)