Ok, but defeat sex is more fun.You are rewarded with sex scenes if you play the game well, the porn is now more integrated into the game than ever before. All you had to do before is stand in front of the enemy and wait for him to do it's thing to see the stuff, now if you don't actually play the game you aren't going to see anything.
This is a much better delivery system, specially considering that the game isn't hard at all, playing well before this change would make you miss half of the scenes. The only thing missing is an incentive to do it regularly, like Kincaid recovers health or fill her special attack bar if you have sex with enemies.
Also, as AxisOfRotation pointed out, this makes the game flow way better now, which will make this game much more enjoyable to play in the long run.
To me, there is no difference between pressing a button to initiate a sex scene and pressing the play button on a pornhub video. The whole reason I got into porn games is because they offer a severely different and more complex interaction compared to other media. With the mechanic of "You win, you get porn (if you want it)," I feel as though I would get the same experience by just playing through the game sfw and then searching "Kincaid" on e621 afterwards. In both cases the porn is player-initiated, but at least with an entirely sfw game I can focus purely on the gameplay.