So...a videogame system that could play DVDs and no one could walk into a store and buy in 2000 due to shortages caused everyone to go out and buy a DVD player that year? Suuuure. Also, CEA player sales figures DO NOT COUNT VIDEO GAME SYSTEMS. Where is the logic in saying people saw a PS2 and decided to go buy a DVD player? No, it's because prices naturally started dropping in late 1999/early 2000.
In the US, the format had been out for three years in 2000 and by then player costs naturally started dropping. In fact five million players were sold in 2000 in the US before the PS2 was released. Also in 2000 almost all of the major studios were supporting DVD, and Disney was starting to release their animated films. That is a major reason for parents to pick up a DVD player, not because some videogame system was coming out.
This all was because the format was becoming widely accepted due to price drops and rental places carrying more DVDs. Also, DIVX had flopped and the studios supporting that naturally jumped on DVD so they wouldn't be left behind in the profits.
In Japan it helped because player costs didn't go down over there. But it helped PS2 sales as people were buying the system just to watch the Matrix DVD.
People like to credit the PS2 with DVD taking off in the US way too much and it's fucking annoying.