I sense there is an age gap somewhere.
Nowadays gamers have grew up with big game productions, with open-worlds and convoluted plots. And they expect similar things on movie adaptations.
In the 90's all we cared about was fun and good graphics. And that's what Mortal Kombat was. Fun, blood, gore and fatalities.
As one who grew up at that time, when Mortal Kombat hit the arcades, when the first movie was released, let me tell you, I TOTALLY enjoyed this. It captures the core of what Mortal Kombat was about then.
Nobody cared about a script. Hell, the only script was a couple of sentences for each character if you managed to finish the game.