Since in Japan, you can not own a beach privately, the Maezato Beach was developed by ANA Intercontinental but is open to public.
It is safe to swim at this beach because there's a net that keeps jellyfishes from coming to the shallow part of the beach. Many of the popular beaches in Ishigaki Island are more beautiful than the Maezato Beach like the Yonehara Beach or Uganzaki Beach but these beaches doesn't have safety nets.
Maezato Beach has been developed commercially. When you go here, there's a lot of beach products and services they offer. You can rent jetski boats, snorkelling gears, floaters, parasols and beach benches. They also offer swimming and snorkelling lessons for a reasonable price. We tried to snorkel here in Maezato Beach but we almost couldn't find any fishes nor corals but it is a great place to practice swimming.