They aren't really focusing on adding plot and game mechanics to the detriment of sex animation. Every update gets a bunch of new animations, but the gameplay is still the same as one of the very first releases, where they already had a quest about gathering fruit.
People just need to be realistic about the scope of these games. Talented game designers probably want to see some life changing amount of money, before they're willing to put their names on a porn game. Copying the gameplay of a mobile game, like Subverse did, is the only way to release the game in a timely manner, if you're working with scraps.