Typically I would agree with a statement like this, but MK is different. The original arcade versions contained silly red spray and spatter. Dismemberment looked cartoonish. Technology changed that, and today's versions of MK can be quite gruesome.
Your comment intrigued me and I decided to see for myself how Mortal Kombat has progressed since I last paid it any mind many years ago. So I watched a few gameplay trailers and I do not agree that MK has gotten any less silly or more gruesome, relatively speaking.
Yeah, there are more pixels on the screen now, but, importantly, the characters don't really seem to suffer. They don't realistically shriek or cower. They more or less shrug off being stabbed through the chest with a giant icicle, or having their bones beaten into dust. It may not be cel-shaded, but it's cartoon violence in capitals. Like Wile E. Coyote being flattened under a boulder. In reality, any one of the fighting moves in MK would absolutely lay an opponent out. Most would never fight again, IF they didn't die from their injuries.
I think what bothers people about these sorts of things is what they themselves imagine that other people get out of them. I don't really care for fighting games, but if I did, I might play Mortal Kombat for the reason that, like the late George Carlin, I like excess in my entertainment. I don't want to hurt people. I won't even squish a bug. But ripping someone's entire skeleton out through their butthole? What a delightfully absurd idea. But the busybodies worry about sickos using MK for porn. Or children being - wait, Mortal Kombat is in no way a children's game, so what the fuck?
Today's MK is no worse than yesterday's Doom. Some people will wring their hands, and 10 years from now we'll all shake our heads in wonder at how naive and prudish we were.