Factual error: Near the beginning when the boat pulls up and the guy on the boat tells the blond convict he's got a beauty 13 foot "Tiger shark" that's up in some sort of sling, the so called tiger shark is actually the same robot mako shark from the rest of the movie, just with stripes on it. Tiger sharks have a blunt rounded nose, not a pointed one like a great white. (00:07:35)
Factual error: A double oven has a double or triple insulating wall between ovens, not a single sheet of flimsy steel. (00:56:00)
Factual error: Late in the film, Susan is wearing rubber aquatic shoes. She goes to her quarters to retrieve the data and decides to electrocute the shark that attacks her. She takes off her rubber wetsuit and stands on it on the metal table to insulate her from the current so she doesn't get electrocuted herself. But, isn't she already insulated by the rubber on the bottom of her shoes? Was this just a reason to get her to take her clothes off?
Factual error: Despite the massive size of the sharks, there's no way that the waist high water would be completely covering the shark. Right before attacks, no one sees a shark until the dorsal fin comes up out of the water.
Factual error: Since the water was always waist high, how could the huge sharks swim inside? Not to mention the corridors... (00:51:10)
Factual error: There's no way those dynamite sticks could have produced anything like the humungous explosion at the end of the film. In fact, the most they would have done would have been putting a hole in the shark's skin. (Proven on Mythbusters.)
Factual error: The so-called 'tiger shark' fed to the Makos is quite unrealistic. As someone already mentioned, the snout is that of a Great White. Furthermore, the teeth are that of a Mako. Tiger shark teeth are very distinct; they resemble a cross between a dagger and a saw blade. (00:09:10)
Factual error: Without wanting to go into extreme details, the genetics and biochemistry of the entire film is flawed. No geneticist in their right mind would even think about using gene therapy - a technique which is not entirely successful yet - to increase the size of the gland. One would use any of multiple techniques to identify and clone the gene responsible for the protein in question. It is cheaper, more successful, and a lot safer and quicker to do. A copy of the gene could be inserted into E. coli and produced on a mass scale in a beaker on land. After the protein had been isolated it would not be able to be given to patients in a pill form because it would be digested in the gut (like insulin for diabetics). (00:05:20 - 00:48:55)
Factual error: The explosion at the end of the movie should have killed Carter, he simply couldn't have survived the concussion wave.
Factual error: When the rescue helicopter approaches Aquatica, the pilot gives his call sign as "X-ray Alpha two eighteen." Numbers in aviation are read individually, so the pilot should have said "X-ray Alpha two one eight."
Factual error: After the doctor returns to her quarters and retrieves some papers, she is trapped on a table or a desk or something and she pulls out a wire that shocks and kills the shark. Isn't it convenient that the jolt ends for some reason right when the shark dies, even though the circuit would have stayed intact and she would have been shocked upon entering the water. (01:23:10)
Answer: They viewed her as a villain because it was her research that backfired and caused all of the chaos, even though none of it was intentional and it was a mistake. But audiences can be ruthless and unforgiving at times. However, the ending did feel like a cheap cop-out that created more plot holes. And many do feel she should have survived and completed her character arc. I don't know why they never offered the ending as a bonus feature on the DVD, but fans started a petition on the Change site calling for Warner to release the original ending. Thomas Jane is on board as well, as he's promoting it on his Instagram account. So that's probably the best way to get Warner's attention if you want to see the original ending.