I think some actions are safe, but I also know (from a zoology perspective and a therianthropy perspective) that intercourse is painful and anxiety-inducing to a lot of animals. Even if pleasure is involved, they’ll still be expecting agony, and I know firsthand that just because something physically feels good doesn’t mean it does mentally. Besides, intercourse and merely the action of humping and/or things that mimic sex is a symbol of dominance among many mammals and that makes it emotionally uncomfortable. Plus, depending on the species, it can be dangerous for the human-bodied individual. Not just from a physical harm standpoint, but from a social and legal standpoint as well.
I’m both an (auto)zoophile and nonhuman, so this sure as hell doesn’t come from an anthropocentric standpoint. I simply think the physical and emotional risks outweigh the benefits. Plus I think you can still have a relationship with an animal without the risk of harming both of you. There are plenty of other things, like courtship, that communicate your love even better than intercourse!
This depends so strongly on the species of attraction that it is incoherent to attempt to impose a standard on zoophilia as a whole.
Nobody’s hurting a horse unless they do it on purpose. It should be fairly obvious that it is in fact John McAfee who was incapable of consenting to the whale. The vast majority of dogs are huge sluts unless yelled at for it.
Cats? Rein yourself in, that one’s tough. Chickens are very popular for some reason, and I don’t think that’s good; they have complex mating behaviors that indicate pickiness and generally aren’t good at communicating with us.
The piece of anthropocentrism you forgot is that “different species” is a level beyond “different culture.”