When we go to see comedians or funny movies, they don't address the wall behind them; they face us. This is why a game's first job is to entertain through gameplay and secondarily through humor, drama, or other traditional entertainment devices. The humor has to be a gentleman. I mean, it needs to be squeezed in around the game.

This quote is saying that it is important for games to be entertaining but the humor should be subtle. It should not be the main feature of the game, but rather should be woven into the gameplay. Games should be entertaining by having fun gameplay first and foremost, and then adding humor, drama and other more traditional forms of entertainment to supplement this. The idea is to not be overly obvious with the humor and drama, but to instead incorporate it into the gameplay in a less intrusive way.