The big point of disconnect for me, on the suggestion that it normalises child abuse, is that there is a lack of conclusive evidence to prove either positive or negative causation between accessability to child porn (real or fictional) and child sexual abuse.
@GarthTheWereWolf gave his input, and from what I had a look at, it seemed like there were studies which pretty much gave the same conclusion of child molestors. In those studies, they found a positive correlation, after they asked child molestors in prison questions about whether real child (note: not of fictional or non-human) porn contributed to a downward spiral for them towards molesting actual children. That said, I'm pretty sceptical, because there's some level of unavoidable confirmation bias with that methodology, and it lacks any input from the non-offending pedophiles. Also, it doesn't say much to the effects of
fictional child porn, which is much more divorced from reality.
On the other hand, there is also evidence that there is either a negative correlation or no correlation at all, which the researchers conducting these studies usually state in their conclusions that it's likely because it acted as a substitute. One of those studies, in particular, found that in every country or city they tested in (Canada, Croatia, Denmark, Germany, Finland, Shanghai, Hong Kong, Sweden and the USA), child sexual abuse decreased or stayed the same when accessability to child porn grew. (To be clear, I'm aware that real child porn is still wrong, because it funds an industry to abuse actual children somewhere in the world. Though, fictional art doesn't have the same implications.) However, it is still just a correlation, and not conclusive proof.
Another consideration to keep in mind is that there is a difference between fetishising real children, fictional children, and cartoonish anthro wolf pups in diapers. I don't believe that an attraction to one would necessarily mean an interchangeable attraction to one of the others.
Also, while anecdotal, I personally know two people who look at cub porn, yet neither fit into the category of 'pedophile' (hence why I'm finding a large portion of this discussion annoying). Instead, they like to imagine themselves as the cub instead of as an adult, which I guess would be a type of infantalism. That in mind, not everyone who looks at cub porn is a pedophile, and none of us know the true proportions of the two consumer groups, or if there is even a sizeable demographic of pedophiles at all.