Unfortunately,uncensored Japanese porn is relatively uncommon.
Not any more. Honestly, that law expired in the late 90s.
Not true. Article 175 is still in effect, and they will arrest people for it. The most recent reprobate arrested for pornography was in 2014, if my memory is right. He took the case all the way to the Japanese equivalent of our Supreme Court and they not only upheld Article 175, they increased his fine. Google it, as I may be wrong on the details.
There's lots of DECENSORED Japanese porn, usually done by the translators in other countries. The only UNCENSORED Japanese porn I've seen comes from places *outside* of Japan, like Pixiv or Patreon. They aren't trying to enforce their law on Pixiv or Patreon, even though the authors may well be Japanese. Japan law hasn't figured out yet that we're occasionally adding the pussies and cocks back
into their porn, and masturbating furiously to 'em, so Article 175 is only causing them lost income.
With 1995 and the introduction of the World Wide Web, I imagine there are lots of Japanese people hunting for non-Japanese porn.
Uncensored means the censoring was never applied.
Decensored means someone has drawn the naughty bits back in. I've seen decensored videos, but that takes a hell of a lot of work modifying each keyframe. Mostly they just decensor doujins and mangas.