How do I delete photos from Apple Photos retaining only those marked as favorite? This should be a fairly easy task to carry out, but I cannot seem to figure out a straightforward way of deleting all but favorite photos from the Apple photos app. One workaround is for me to create a smart album to pool all favorites together --> export --> delete all photos --> reimport, but this definitely is a waste of time especially with large libraries.
Am I missing something here? Any ideas?
You can do this using smart albums.
Unfortunately the gif I made to show this is to big so pictures will have to do.



go to all your photos and select all of them (cmd+a).
Create a new smart album for your selection

In the popup select photo is not favorite as filter, you should see the number of matches.

In the smart album are all your photos not marked as favorite, select them all (cmd+a) and delete them (cmd+backspace).

Go to all your photos, only the favorites remain.

Empty the trash in the photos app to remove all deleted non favorites.