The quality of cricket of the 2005 series is sometimes seriously played up. Granted that McGrath provided a master class at Lords and was virtually unplayable throughout that test, and that Jones and Flintoff were frequently as good as it got, but there was plenty of poor cricket in that series from both sides. Australia, with the exception of Shane Warne were frequently atrocious with the ball, in the first innings of some of those tests when Warne wasn't able to get much turn out of the wickets, that Australian attack was even more toothless than the one that played in 2009, to the point where 'I thought England really have to **** up in order to get out to this lot'. Sure enough, they almost always did because a) they are England and b) because then just like now they were a poor batting outfit.
It's all fine to look at the players on both sides and say that there were better players on paper then compared to the ones now, but just because the names were more recognized it doesn't mean the quality was much higher. The fielding that series was absolutely atrocious as well, certainly nothing compared to what we've seen in the recent series. 2005 was a great series no doubt, and better than the sequel, but both sides underperformed that series (I'd rate England's performance in SA in 2004 higher than their performance in that series) and Australia were inferior to almost any Australian side that we had seen play in the 5 years preceding it this decade(with the exception of the side that played India in 2003/04).
The brilliance of Warne, Flintoff and Jones in that series (and occasionally Trescothick and McGrath), sometimes overshadows how mediocre the rest of the players were.