Most mirrors arnt really aerodynamic tho (Tho my new ones are)

Same as 3dr bumpers, slab front and quite flexible, yes the air goes thru the holes and around it, but its soft enough idve thought itd get pushed in, same with mirrors, which are often jus slabs n only held in place by spring loaded clips.

Obv they do stay in place, but i jus wana understand why (in a semi-technical way), lol