Well, if you want to get technical, that's indirectly moving into a discussion about 'fetish' because a lot of folks who entertain with anime also have specific fantasies. But it does indicate to me more the issue some folks might have with content variety and target audience.
Pictures of any kind are to me a second best replacement for the real thing. Both photography and erotic drawing portray archetypes exaggerated so as to be pronounced and communicative of some type of idea. It is the entertainment of an ideal, or the advancement of an ideal about eroticism.
To me, the failing of anime as eroticism is the way the mouth is typically drawn. That's why I don't like the association my stuff has gotten with anime, but that's not the point. The mouth is not just the object of a sexual urge, but in my opinion the core of what makes human expression unique and human. A wide range of emotions and thought can be expressed with our mouths and to me it is one of the most capable vehicles for expressing eroticism.
What I think is that it does not matter what the medium is, it depends solely on the viewer. They take the image they see and make it do whatever they make it do in their minds. It is, flesh or flash, still about conjuring an idea in the mind of the viewer. If they are only receptive to a certain range of ideas, and mine do not succeed in emulating those ideas in their mind, the my work has failed as eroticism in that instance. But it works conversely as well in that some people need very specific forms of stimulation when we are discussing using images as a replacement for the real thing and invoking arousal in this way. Physical stimulation has chemical components and it is totally different. I don't think it's possible to capture the visceral reaction I get when I feel a woman's body pressing against my own with an image, no matter how overly exaggerated the features of that image appear, because it is not even remotely the same type of arousal.