Anyone curious, about making sashimi out of fresh-caught fish, it's actually somewhat okay in this specific circumstance. They specifically mention it's yellowfin which are top tier predator pelagic fish, IE ones that live almost entirely in deep open ocean on closer to the surface (IE not bottom feeders), and almost exclusively eat other smaller fish, and not really much else. This makes them far less likely to get parasites. If you're catching it yourself in that circumstance, and know the area, then it's usually pretty safe and you don't HAVE to freeze then defrost them, but you probably still should anyway.
Pelagic fish and farm fish raised in well-regulated farms, are about the only times you would ever risk eating sushi or sashimi that wasn't frozen at some point to kill the parasites, like 99.9999% of sushi-grade fish is.