No slap intended - just a couple of neurons waking up to recall the Fluid Dynamics class and recalling seeing dye flow tests on small scale models for supersonic designs operating at low speed and high angle of attack in water tunnels to visualize vortex flow.
The one that people get wrong all the time is thinking that rubber is compressible; it is stiffer in compression than steel is. However, it's more elastic and can, if allowed, flex enough to get out of the way. Confine it and the difference becomes really clear. People think air is compressible because they can use an air pump and compress it - but that's only because it is confined. Let it have freedom to get out of the way and compressing it is really difficult.