Fable adds guard rails like cyber refusals to mythos. Mythos is the starting point for fable. Same model family.

They're very similar models though, just with different safeguards and restrictions in placae around particular use cases.

I guess the underlying issue is that there is this model that is very capable, but it's being hobbled because of a fear of abuse. It may well be justified, but for a legitimate user any restriction just makes it a worse product and after all the puffery around how good it is (and some practical experience of how good it is) it's a pretty shit experience. "Here's our best model, no you can't really use it".