>>1658382>for some reasonQuestionable personal appearance choices (shitty tattoos, implants, tacky makeup), lack of acting talent/enthusiasm/emotion, overall unwashed feeling to them, tendency in many cases to be profane for profanity's sake (the shit they say, faces they make, middle finger for no reason, etc.) Feeling of shame on their behalf (the way some people tend to feel when watching someone do something that embarrassment and/or personal pride really ought to prohibit them from doing.) Basically everything about most porn actresses says "this person is really unpleasant" and it makes it difficult to feel any sort of attraction to them, sexual or otherwise.
Drawn stuff is fine because the human element is removed from the act. It's purely fantasy, every aspect of it was within the creator's control. The artist didn't have to work around the reality of a typical porn budget or the skeevy women the industry attracts, and even if the character has a backstory it's probably way less creepy and gross than a porn actress' life. You don't have to worry about empathy or shame strangling the life out of your boner.