Looks like he mis-judged the loop; gotta give yourself enough altitude to pull out at the bottom. To be fair, it’s more difficult to judge altitude over the water.
Marine Corps F/A-18 had a similar mishap at the El Toro Air Show back in 1988; the pilot, Colonel Jerry Cadick, was severely injured, but survived. He passed away in 2015. Afterwards, the liked to joke that he “broke” a “perfectly good F/A-18.”
https://www.youtube.com/watch?v=IFSSJSFtd2k
https://www.youtube.com/watch?v=alo_XWCqNUQ