There's not much wrong with the way Great White is made and the acting is fine. It's just that this tale has been told many times before, and this movie offers nothing new.
There has only been one good shark movie: Jaws. All the others are formulaic, predictable affairs. This is true even when the production crew try to spice things up with a bit of fantasy, such as with The Meg. That particular masterpiece featured a megalodon instead of an extant shark, but it was the same story, just with a bigger beast.
The same is true for movies about crocodiles and unfeasibly large snakes.
The only interest lies in spotting who from the original cast will survive. It's usually safe to choose the lead female actress in the movie. Only choose the lead male actor if he's had a troubled past and needs redemption. Be careful, though, because they often have to give their lives in heroic fashion to save the female lead. If there's a nerdy or mousey actress amongst the cast they'll sometimes survive too. Everyone else will be eaten.
If you keep a cutting of the above paragraph handy you'll be covered for 90% of such movies.
I've already given away the plot for Great White, but for the avoidance of doubt: five people are stranded on a life raft and are being hunted by sharks. Some live, some die. It's not badly acted and it's visually appealing, but the plot is what you'd expect it to be. I didn't hate this movie and I've seen far worse, just don't expect too much from it.
You may think you've spent 91 minutes being mildly entertained, or you might wish you had the 91 minutes back. It depends what floats your boat, although I hope your boat floats better than the one in this movie.
I'm glad I'm not a professional reviewer because there's no way I could find a thousand words to describe this movie. A thousand word review is probably more effort than the scriptwriters put in to Great White.