Exactly my thoughts, the author talks about S&P500 initially (which recovered "fairly" quick after the dotcom bubble burst) and then uses a different index to exemplify how the dotcom bubble took long time to recover.
While the peak-to-trough drop wasn't as bad as QQQ's, the S&P 500 still managed to fall something like 40% from its dot com peak in 2000 over two years, and didn't fully recover until 2007. (And of course 2008 sent it right back down again for another five-ish years).
