Along with that, if you consider why people use low spoke count wheels, it might not apply much to riding fixed. In the road world, they are usually boutique wheels that are designed to be more aero and/or lighter than standard-built wheels. I opt for reliability on my fixed.
Speaking of... I think the new Mavic Ellipse has 20 spokes front and rear. It is a strange wheel- a bit heavy and clincher only? And they run about $450/set.
For many of us, that would cost more than the rest of the bike, in the fixed world.
I tossed a 20 spoke radially laced front on one of my bikes- no problems, but I think twice before riding off curbs, etc.