It's worth noting that the image in question is
not pornographic. It's entirely possible to depict nudity and for it not to be pornographic. A passing familiarity with the manga or anime series would correct your misconception.
Further, even if it were pornography, researchers (see Patrick Galbraith) have shown, through ethnographic field work in Japan and studies of the fans that they do not interpret these images to have the real-life referents of real children. Rather, they are symbols that only refer to other symbols and tropes. In other words, it's a "2D" phenomenon, and the naive interpretation that it is a "3D" one for the people who enjoy it is insufficiently nuanced and incorrect.
It's also dubious whether such content counts as "encouraging pedophiles" in itself. As much as, say, BDSM pornography may encourage rapists, that does not mean that people enjoy it for other reasons - and there is an empirical reason to think that most people do enjoy it for other reasons. The blame lies on the consumer of the material and their thoughts, not the publisher who believes with good reason that the most common reading is not "encouraging pedophiles".
Further, even if it were pornography, researchers (see Patrick Galbraith) have shown, through ethnographic field work in Japan and studies of the fans that they do not interpret these images to have the real-life referents of real children. Rather, they are symbols that only refer to other symbols and tropes. In other words, it's a "2D" phenomenon, and the naive interpretation that it is a "3D" one for the people who enjoy it is insufficiently nuanced and incorrect.
It's also dubious whether such content counts as "encouraging pedophiles" in itself. As much as, say, BDSM pornography may encourage rapists, that does not mean that people enjoy it for other reasons - and there is an empirical reason to think that most people do enjoy it for other reasons. The blame lies on the consumer of the material and their thoughts, not the publisher who believes with good reason that the most common reading is not "encouraging pedophiles".