I've seen this as an LPT or similar posted on Reddit. I think it helped save a life in the New Year pre-pandemic.
I'd stopped at a picnic location near a rocky Atlantic (European) coastline with my partner. It was a picturesque location but the sea was inhospitable - huge swell and waves that just looked violent. We'd sat down at a bench with a view of the sea and set out our lunch. At some point after that I noticed two people in the sea, maybe 30-50m out. They were bobbing about in the swell. Initially I was confused. It didn't look right but my mind tried to make explanations - maybe the locals just swim out there in crazy conditions? After some time it became clear that they were in trouble, I guess that's when the "drowning doesn't look like drowning" advice came to me. Luckily the beach (tiny strip of sand between cliffs) had a well-labelled sign with an emergency number that I called and managed to ask for an English speaker and described the situation.
Whilst waiting for the response one of the people in the water started trying to tow the other towards shore but made no progress. They kept disappearing behind large waves and at some point I could only pick out one of them, then I saw a pair of shoes or sandals floating then I saw the other person face down in the water, occasionally visible behind the swell. There was some dithering where a local official came to the beach to check out the report but eventually we heard helicopters and one person was rescued and the body of the other recovered.
It turned out there was a group of three tourists, two sons (teenage/early 20s) and their dad. A local had taken them to a fishing spot - a flat rock that spanned out towards the sea close to water level. A large wave had washed the dad and one of his sons out to sea. The dad died. I witnessed the other son - who hadn't been washed out to sea - being interviewed by police, as utterly distraught as i've ever seen a person, understandably.
Looking back on it I should have realised the severity of the situation sooner but perhaps without this advice I would have left it too late and neither would have made it.