The dude averaged 17 in his rookie year when being asked to completely carry a sad team on the offensive end.
The fact that he was being asked to "carry a sad team on the offensive end" is exactly the reason why his 17 PPG wasn't that impressive.
In Avery Bradley's first three seasons when he was playing behind Rajon/Ray/Paul/Kevin, he consistently averaged around 12 points Per 36.
Once Ray, Paul and Kevin all left, Bradley saw a significantly increased role - his scoring average jumped to around 16.5 Points Per 36 over the next three seasons due to his increased role in the offense. That's an increase of around 40% to his Per-36 scoring rate.
Over his first three seasons in OKC, while playing behind Durant and Westbrook, James Harden averaged around 17.1 Points Per 36. Over his next four seasons in Houston (where he was the #1 guy) his averaged jumped to around 26.9 Points Per 36. Why? Because he was the #3 banana in OKC and the clear #1 banana in Houston. A drop of around 57%.
Kevin Love averaged 25.9 Points Per 36 as the #1 man in his last season in Minnesota, and that dropped to 17.5 Points Per 36 when he became a #3 guy in Cleveland. A drop of around 48%.
Ray Allen averaged 23.6 Points Per 36 in his last season as the #1 guy in Seattle, and that dropped to 17.5 Points Per 36 when he became the #3 guy in Boston. A drop of around 35%.
Chris Bosh averaged 23.9 Points Per 36 in his last season as the #1 guy in Toronto, and that dropped to 18.5 Points Per 36 when he became the #3 guy in Miami. A drop of around 29%.
It's simple common sense - being the #1 guy on a bad team is gong to INFLATE your stats, not DEFLATE them. So Okafor's average of 17 PPG on one of the worst basketball teams in history (which had no other competent scorers) is not a grand achievement. Not saying it's a bad thing, but it's not exactly "wow" worthy either. If he were on the Suns or Wolves sharing the scoring load with Bledsoe/Knight or Wiggins, he probably would have been lucky to average 14 or 15 PPG.
Just basic basketball logic there.
Plus his defense is extremely underrated IMO. 1-1 he is at least serviceable
No, it's not and he isn't. He had the second worse defensive RPM in the entire NBA, with Enes Kanter (a guy infamous for being the worst defensive big in the NBA) being he only guy who ranked worse. His defensive rating was no better either. Ever advanced defensive statistic out there will tell you that he was an utterly atrocious defensive player - one of the worst defensive bigs in the entire league.
Al Jefferson, despite his reputation, was never CLOSE to being that bad on defense.
Oh and you can't blame the team's shoddiness for that stat either, because Nerlens Noel (who played on the exact same team) had one of the league's top defensive ratings. There is no way to sugarcoat that.
and gets rebounds at a decent rate.
No, he doesn't.
Okafor's total rebound rate of 12.8% is utterly woeful for an NBA center - even more so when you consider the sheer size and physical presence he has.
Brook Lopez has been known for being one of the worst rebounding centers in the NBA for years now, and he had a rebound rate of 15.8% his rookie year, and 13.1% for his career.
Kelly Olynyk (who is far from a great rebounder) had a rebound rate of 13.1% in his rookie year, and has a career rebound rate of 12.4% - Okafor has been rebounding about on par with KO, which is absolutely embarrassing for a 6'11", 270 pound monster who lives in the paint.