I think everyon'es comparing apples to oranges.

Saturn yellow/red labels = some panties, and a bit of animated nudity. Something you might see in a normal anime.

PC hentai games -- total filth, and they make up like 70% of the PC game market in Japan, and probably more like 90% of the Japnaese-made PC game market.

The only really nasty things I"ve seen on a system are those hack SFC roms (that are just pictures) and the aforementioned games, which could easily fall into the PC category.