I don't think it's fair to say that Pioneer blocked the release of porn movies on LaserDisc. In fact, most (if not all) of the hardcore porn LDs in my collection were manufactured by Pioneer USA. They didn't draw attention to themselves by placing the Pioneer name anywhere on the disc, but it's obvious from the mint markings who the manufacturer was. I still find it amazing that a mainstream company would get involved with pornography in the first place, especially considering Sony's anti-porn stance.
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