“Deprecated synonym” means the same thing as “Non-preferred synonym”.
Clitocybe phaeophthalma is a legitimate name; it is synonymous with Singerocybe phaeophthalma; but it’s a (slightly) inferior name.
Are deprecated synonyms still synonyms even after they have been deprecated?
Why do you have to deprecate Clitocybe phaeophthalma (Pers.) Kuyper when it is a “good” synonym. I don’t see anything wrong with it and I don’t see any reason for its deprecation! Or, is it something here what I should know and don’t know?