There is a possibilty that this is not meant to direct air, rather pull air away.
Can't really tell from this picture, but I can see that happening, if a negative pressure is built up behind and inboard of that bracket. Since there is a positive flow from ram air from front of car and even engine bay.
Just an observation.
Having said that, if this is an air "director/deflector", I would say some sort of ducting towards the brake would make this more efficient.
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