Here is a link to a OSMCha filter for a user who has been adding a lot of beaches. Although most are near water, only some look even plausible. Also, the beaches are almost all mapped as nodes, and the changeset comment is always the same “add roads, add parks, elements and building”
Perhaps others could review and comment. I have deleted some of the beaches where it was obvious (based on the Bing imagery that the mapper cited as a source) that they didn’t exist.