Seriously?
Considering the relative youth of Bale, Kaboul, Walker and Rose, our squad definitely wasn't as good as theirs at the time (I could have sworn that Walker joined the year after that anyway and Gudjohnsen wasn't part of the squad when Keane made that statement). Also bear in mind that back then Arshavin actually looked like he gave a brick and on that sort of form was one of the best players in the country. And nobody in our squad came close to Fabregas or Van Persie.
They finished above us that year, scoring more goals and conceding less goals than us. The same with the year before and the same with the year after which proves it wasn't a one off. There was no reason to believe our squad was as good as theirs at the time.
On the money
They had much better players than us that season, especially at the time of the quote (early in the season) before the likes of Bale really emerged.
Fabregas was (and still is) a near world class player and Arshavin was still on good form. We were never in contention for 3rd either but battled it out with a still-gelling-in lotto winners team