A few years ago I was swimming in a lake and a guy was doing this in chest high water. I asked if he found anything but he had headphones on.
I follow several metal detecting social groups and see reports from many detectorists that have submitted some amazing finds.
I am a London mudlark with official permit, and on my twice yearly trips to London from Texas I can’t wait to get down to the shore at low tide to search for interesting items. While other mudlarks on Facebook groups like Thames Foreshore Finds love metal items and coins, and have even found gold nuggets recently, I love the ceramic pieces that are everywhere on the shore. Medieval pots that still show the fingerprints of their makers, Roman tiles, pieces that were from buildings destroyed during World War II, and more are absolutely fascinating to me.
About 8 years back there was a show on National Geographic called Diggers. A couple of clownish Metal detector guys digging up various sites. There were some interesting finds over the three years of the show.