[Matra et Alpine]

That's why it might be bug-deflector ?
remember so far we've not got a definitive answer and won't till Wouter comes back
By deflecting upwards it creates a 'curtain' of air which will rejoin the body laminar flow above the screen. Closer to the screen and the 'curtain' would maybe only join half way up the screen.
The 'curtain' could be to keep that airflow from lifting the wipers or to blow the bugs by