Not full up retro, but I remember one dial up BBS service in my local dialing zone had a 6 disc CD changer and the sixth disk was loaded full of porn. Downloading at 14.4kbps meant getting about 100kb per minute, but since even the high quality stuff was only 640x480 that wasn't so bad.

The big difference on the 8-bit micros is no Internet, so you would have to find someone physically selling the disc, which was very hard to find. Plus digital scanners were extremely expensive professional gear and digital cameras basically didn't exist. Production was seriously bottlenecked. Still, like life, porn finds a way.