Hm. But terror is a very strong word. Mostly, in scary games, I feel apprehension rather than outright terror. It is important to create that feeling of expectation, of coming horror.
Speaking of revulsion, Dead Space certainly relied on that a lot (transformation scenes, blood, amputations, puke, tentacles, visceral gurgling and screams, "meat" on the walls and floors etc.). Funnily enough - because of its reliance on jumpscares - the apprehension I experienced was less terrifying and more "man, I hope I can aim at the next monster that'll jump at me quickly enough".
One thing I find interesting when looking at System Shock 2 (again, yes

) is that - while it employs a lot of gross stuff with The Many, the worms, eggs, fleshy growths, mutants etc. - some of the to me most apprehension-inducing situations were much more... clean. Some of the scenes fighting/hiding from robots or cyborgs are not revolting but still manage to ramp up the worrying.
But then I guess King put revulsion as the lowest of his three rungs of horror, so it makes sense that it's really not
necessary to get the desired effect. It's a "backup".