With the snake already having bitten a visitor and the knight robot killing the other. Do you feel it took away from the impact of Yul Brynner's gunslinger running amok? Would it have been better if it was more of an "out of the blue"-moment that he, only, malfunctioned and shot the main character?
Moviegoers are already expecting that a robot called "The Gunslinger" is going to end up turning on humans. Having him just kill the protagonist and the film ends would probably be hard to pull off in a satisfying manner, at least in the hands of Michael Crichton who clearly preferred scenarios where *everything* goes to hell, not just one freak accident that claims a single victim.
But wasn't it a given beforehand that the gunslinger is the one off? All the movies frontcover art certainly shows it and in the movie it's not exactly subtle either. He wouldn't have to kill the protagonist and the movie ends it could've transpired just as it did minus the other androids malfunctioning.
The thing is that a widespread robot malfunction means humans in the park were overwhelmed and the protagonist had no one to turn to for help.
It isn't impossible to make an entertaining movie where the Gunslinger is the only malfunctioning robot, e.g. the protagonist could try to enlist the help of other humans and "good" robots to try to stop him. But the tone of such a movie would be a lot less bleak and probably not something Crichton would be interested in.
That's true. But then at the same time it also detracts somewhat from Yul's robot. The walk, talk, stare everything that made him so uncanny are now really not all that essential parts when others malfunction anyway.