It's a solid parody of the utterly broken modern genre of silly anthropomorphized shark movies. That the cast take it seriously in their cliché roles makes it a bit of a satirical gem for B movie lovers, the fx are ok for the budget, the referntial cues and obvious plot vehicles are relentless, the pretense of tension is fun, the ending is suitably ludicrous, it's a joy to turn your brain off for.
Don't take it seriously, and bring the good popcorn and a sense of humour. It is a comedy horror in-joke, basically designed to annoy pretentious movie reviewers by having a touch of polish, after all.
Don't worry, be happy, and watch this 15 certificate kids movie, chomping it's way through imprudent characters with your holiday brain. It's spot the tropes time.
It's ok if you nod off, or decide to lose yourself the eyes of your best girl instead, this is a drive thru movie, and a good bad one.