Bowen is a one-dimensional defender. Great at lockdown, but mediocre in other aspects. He's also very unremarkable as a defensive rebounder. The true all time defensive greats like Jordan, Pippen, Russell, Payton, Olajuwon, Robinson were multi-faceted defensive studs. Bowen is simply not in that class and never will be.
And while blocks and steals may be overrated to a degree, these are also plays where you are effectively stripping your opponent of possession. They also frequently lead to fastbreaks. Bowen is lackluster in these areas. He's lucky to be in a great system where interior defense is so valued that perimeter players can really get into wing players and know they have help behind. Put him in Sactown with their team defense and no way are they better defensively than with Artest...