The current Picard 2.3.0b1 is incompatible with macOS 10.12 and fails to launch:

[53512] Error loading Python lib ‘/Volumes/MusicBrainz Picard 2.3.0b1/MusicBrainz Picard.app/Contents/MacOS/Python’: dlopen: dlopen(/Volumes/MusicBrainz Picard 2.3.0b1/MusicBrainz Picard.app/Contents/MacOS/Python, 10): Symbol not found: _futimens
Referenced from: /Volumes/MusicBrainz Picard 2.3.0b1/MusicBrainz Picard.app/Contents/MacOS/Python (which was built for Mac OS X 10.13)
Expected in: /usr/lib/libSystem.B.dylib
in /Volumes/MusicBrainz Picard 2.3.0b1/MusicBrainz Picard.app/Contents/MacOS/Python

I reportedly runs on macOS 10.13 and later.

See also https://community.metabrainz.org/t/picard-2-3-beta-1/461345/46?u=outsidecontext