If you've actually played the game, you'd know Fate Stay Night isn't a porn game that is about it's sex or nudity.
That content is relatively minor, it's a heavily story and dialogue based visual novel game.
The Fate anime had two problems - one is it's pacing, at times it's perhaps a little too faithful to the game and get's very wordy and it just really kind of drags at times.
The second probem is, it's the Fate storyline of F/SN - arguably the simpler and more generic of the games three storylines. The other two storylines, Heavens Feel and especially Unlimited Blade Works are considerably more interesting, but the problem is you can't just make an anime based on either of them because they rely on the Fate storyline to introduce characters and set up their personalities and motivations, etc. They also don't showcase the full range of servants the way Fate does.
The anime kind of does itself a disservice by showing hints of those other storylines, since it gave gimpses of interesting things it wouldn't cover.