I've probably said this before, but I'll say it again. Obviously, the difficulty, consistency, and quality of quizbowl questions changed drastically between the first stage of my playing career (mid-'90s through around 2001) and the second stage (2004-2010). It is understandable that if your only exposure to the "pre-modern" phase of the game is through glancing at old packets, you would jump to the conclusion that teams of that era were a joke by contemporary standards.
In my view, however, that conclusion would be a mistake. From the perspective of someone who played at both tournaments, the actual experience of competing at ACF nationals in 1997 was basically the same as competing at ACF nationals in 2010. I've explained elsewhere my views on what could be called the phenomenology of high-level quizbowl competition, and what sets the best players and teams apart--I think those phenomena were essentially constant throughout both eras.
I will say that if the criterion is "how good a given team was vis-a-vis its contemporaries," then it's my opinion that the 1999 Chicago team was the best of my career. I don't know what kind of records exist, but my recollection is that the A team that year essentially went undefeated, including at both ACF nats and ICT. In my (possibly biased) view, that team was head and shoulders above the other teams of the time in a way that no other collegiate team of my career was separated from its competition.
Ex-Virginia, Ex-Chicago, Ex-Stanford