Coronal mass traveling at a higher speed "sweeps" what's before it. You can see the spiral shape, and you can probably figure out that the stuff is slowing down as it moves outward.

Watch this occasionally for a few months and you'll get the idea, although solar activity is slowing down somewhat (as expected).

https://www.spaceweather.gov/products/wsa-enlil-solar-wind-p...

If you carefully re-read what GP wrote, you'll see there's no reference to Earth's orbit or 1 AU in there. GP wrote about the solar wind scattering cosmic rays when it reached some point in its outward travel.