Climbing harnesses are usually sitting harnesses that are more padded around the legs and back than work harnesses are.

The bigger thing, though, is that suspension trauma typically happens when you're purely hanging. The amount of time you can hang in a void in a work harness is way, way shorter than the amount of time you can bounce off a wall in a work harness, particularly if you're able to support much of your weight with your feet.

For climbers, the main worry would be hanging around if you're somehow incapacitated from a heart attack or having been knocked out somehow, because workers are a lot more likely to be suspended over a void than climbers.