Sales would have STILL declined between the 1997/2000 gold rush and now. Period.
There is a lot more to do online now to take away people's attention than porn alone.
Could the percentage be less than today if were not for all of those other things mentioned? Sure. Could the adult business, industry wide, helped to prevent this by using DRM or other technology? Yes. Could affiliate programs not given away access to their entire members area helped slow the spread? Of course.
But regardless, the sales would have still declined, and people would still be blaming the boogie man of 2012 for their lack of adaptation or innovation 10-15 years later after the boom.
