Are there any examples in the history of physics where a phenomenon was considered by the physics community to be not explainable by classical physics and needed a quantum explanation whereas some time later it was noticed that this claim was wrong (perhaps because for instance one "over-idealized" the system, neglected boundary effects or did some other mistakes when "proofing" that there is no classical explanation), i.e. that the phenomenon has indeed a classical explanation? Let me call those effects "pseudo quantum effects" for short.
Are there such pseudo quantum effects which were today common misconceptions (i.e. where people think that one needs a quantum description but doesn't really do it...)