This is the best in human nature. It’s the same impulse I see in children’s playgrounds. Whenever a child cries or is in trouble all the parents, many of them complete strangers, look up ready to rush over to help if needed.
Outside of books, I’ve never heard of a group of people forming a human chain in the sea to save someone before. Whoever thought of the idea on the beach that day saved that family. I love it when humans come together to help others.