Lolicon is obvious, it's simulated kiddy porn for sick fucks what want to fuck little girls. (No judgment.
) But shotacon... the vast majority of it I've seen (and as a regular nhentai user, I've seen *a lot*, the last few years it's been taking over the hentai manga/doujinshi scene to nearly the same degree as NTR) is still super male-gaze-y. Like, yeah, there's a little boy there, but the focus is still very much on the women. It feels like, whereas the fantasy being serviced with lolicon is fucking little girls, the fantasy being serviced with shotacon is fucking grown women *as a little boy*, and I just... can't wrap my head around why that's appealing to anyone (let alone apparently to half of Japan).