I'm not sure I totally agree with this, but I'll go with it, and expand upon it even more.
Those climbers who primarily boulder, that's climbing without a rope, fairly close to the ground, are better still. Because they work on insanely difficult problems and fall all the time.
No, he's right. Boulder falls are nearly always soft, and certainly aren't painful. Usually they're only a foot or so onto a pad. It's actually pretty rare to come off from high up and miss a pad.
Granted, you can still break things. But it still works out safer on a per-hour basis than Volleyball.
Those climbers who primarily boulder, that's climbing without a rope, fairly close to the ground, are better still. Because they work on insanely difficult problems and fall all the time.