If you're playing so conservatively, you should at least be giving up a lower FG% overall. It seems Portland has the worst of both worlds, they don't get turnovers, and are only middle of the pack in opponent FG%. But one area the Blazers have really improved in is FG% in the paint. They are 3rd best in the league within 55.3% feet. Ironically they have totally flip-flopped what they were earlier in the season, when they were one of the best in the league at defending the 3. They are not 3rd WORST in the league at defending the 3. Guarding those point blank shots is the only thing they do well. 5th worst 5-9 10th best 10-14 (fewer shots taken in this range than any other category. 3rd worst 15-19 12th worst 20-24 3rd worst 25-29
The flip side to their defensive % within 5 feet, is that they give up the 2nd most attempts. The Lakers and Blazers really lead the pack in that catagory. Portland has 1669 attempts in the paint, and the 3rd place team, the Celtics 1597. So they allow a lot of penetration, and high % shots, so you can't really consider it a strength. So basically, they suck at everything on defense. They allow penetration, don't get turnovers, and give up a high % on 3pt shots. I don't think there's any reason we should be one of the worst defensive teams.
The analysis ignores the effect this style of defense has at the other end in transition. By forcing opponents to shoot mid-range jumpers rather than 3 pointers, it leaves a clear path when we rebound. This is why we average 4 more assists (which is 8-12 pts + free throws) per game than our opponents.