[NSFW] Coprophilia, Necrophilia, Zoophilia are frowned upon as ill, Why? What is the reasoning behind it?

These philias are sexual desires & are not harmful to another creature, whether human or animal alike or an inanimate object(corpse). If one has a sexual desire to show affection by tasting his/her lovers feces (with consent), & if a sexual lover, who gives consent to his partner before death, to allow the partner to use the cadaver for his/her sexual pleasures, (has nothing to do with respect for the dead, as consent was given) or if an animal who is being sodomized by humans or oral play, or visa versa, furthermore, does not show resistance, but pleasure (which is consent), what would be the reasoning by deeming these actions as ill, when there is no physical harm being done & it’s not effecting anyone else as it is not done publicly?