Playoff teams are the top 10 ranked teams and Pittsburgh was 16th, Tampa Bay 18th.
On the flipside, Florida (11th) and New Jersey (12th) are ranked as playoff teams but did not qualify. Florida was 10-6 and had a fine season but did not qualify because of tiebreakers. New Jersey should have a better record than 7-9 based on stat rankings but the Generals were 2-6 in one score games, and the other 3 losses were to playoff teams: lost by 9 against Baltimore, 12 against Memphis and 14 against New Orleans.
Say what you will about the close losses, but the bottom line is that a true playoff team would have found a way to win more than 2 of 8 close games.