It has nothing to do with aesthetics. The theory is that having the rotating force of the wheel on the brake acting towards the fork, rather than away from it, increases the rigidity of the braking action. Manitou also adopted it in later times, so did Orange with their rigid forks in 1999.
I think the only argument against it is that people think it looks odd. Nobody thinks it looks odd to have the rear brake behind, rather than in front of the brake posts though.