No, not really.

What does it have to do with adult content, though?

Games like Halo and Uncharted will sell tons no matter how low their reviews scores are.

But same with Mario Kart and Smash Bros. These games will sell regardless.

I think you have it a bit backwards. Take GTA for example. One of the reasons that series is so popular is because it has such an amazing track record of quality. New releases are consistently reviewed very well. Fans buy the game anticipating a great experience because of this. Now if a new game received poor reviews, it probably wouldn't deter too many people, but several games in a row of diminished quality and suffering metascores would probably start to impact sales in the long run.