The Raiders defense seemed OK. They were competitive on most of their games.
However, for anyone paying close attention, Tampa's defense was worse than it seemed. They started off like gangbusters the 1st 4,5,6 games. The stats from those games dramatically raised the Bucs D rankings.
Then they trailed off badly. The last 10 games or so, they hardly got any sacks, interceptions, and fumbles. If they started anywhere near the middle of the field, they were going to give up points. When it came to crunch time in the 3rd and 4tt quarter, they would often fold. They were a very average D.
The D also made mediocre QB like Prescott, backups, and rookies look like superstars. They didn't face too many top 10 QBs.