AKAAB, I think that is a good idea. If enough of us declare we've stopped listening to 121.5 over ATC freq it could cause congestion. Perhaps once it starts causing ATC problems they will make the effort to triangulate/ report those responsible.
I heard Maastricht triangulate a Dutch aircraft a few days ago for music being transmitted from their location on 121.5. This proves at least some are able to triangulate.