They selected Wilfork because he dropped to them. Everyone that is succesful, looking back, can be said to have filled a need, but Seymour and warren both played nose sometime and there was a lot of doubt whether Wilfork, who played a penetrating DT in a four man line, would be able to adapt his game to NT.
They certainly had other needs in those days, including linebacker for years and cornerback, which was in worse shape then than it is now IMO.
Once Seympur and Warren left, they certainly had more of a need on tthe DLine than before, yet they drafted no big linemen for years.
A reasonable argument, but one that is mistaken for a few reasons.
First, Ty Warren spent 2003 demonstrating he was nowhere near an NFL caliber NT. Seymour was reasonable at it, but he was so dominant at DE that playing him anywhere else was a waste of his abilities. Aside from that, NE didn't just lose Washington in 2004, they let Bobby Hamilton go as well. If either Warren or Seymour moved inside, DE depth was as problematic as NT.
More importantly, you need to take a more holistic perspective, viewing each season as a singular event. What positions were drafted the years before and where they were selected has limited impact on whether something was a need or not. That influence is limited to the fact that a good drafting team usually doesn't need to keep hitting the same position several years running.
Take 2004, for instance, despite investing two first rounders on the DL, they had such a dominant and deep roster that there were only two positions that even had the potential of allowing a rookie starter, NT and RB. Unsurprisingly, if Wilfork hadn't fallen, the plan was to snag Stephen Jackson, who they still tried furiously to trade up for. And when he dropped off, NE quickly moved on to Corey Dillon.
Sure, no DT was selected in the first until 2014, and while I suppose you could view that as a commentary on need, in reality is was more due to a more rapid decline in other areas of the roster. In 2005, LG was by far the biggest need on the team. In 2006, the offense was getting old and needed some revitalizing. In 2007, the back end of the secondary was either old or inconsistent. By 2008, the DL might have been getting up in age, but CB and LB were significantly thinner.
2009 was the first time DT really was moving up the checklist and... low and behold.... they drafted a DT with their second overall selection!
I actually expected NE to snag a DT early in 2010, one of the few times they threw me a curve and not only went at a position I didn't view as a need, but avoided one I considered a need entirely*.
In 2011, due to stumbling on Love and Deaderick, I thought OT and RB leapfrogged DT. And on and on and on....
One other thing. The (*) is there because the one feather in the non-need cap is LB/DE. That was a need for years before the team did much of anything about it. I still can't understand the reluctance, but I recognized it enough to assume it just wasn't going to happen early in the draft.
Fun discussion!