Entirely different software stack.
For example, when Tesla detects that you are about to accelerate into a human or a wall, they slow down the acceleration so that you have time to react, but they don’t stop it altogether.
That’s very different from FSD’s decision-making process.
It's emergency breaking. There shouldn't be differing results on whether you paid an extra $8000 usd or not.
FSD does not advertise better emergency breaking as a feature. (Last I checked anyway.)
Most if not all vehicles for sale will plow right through a styrofoam wall like that regardless of whats painted on it.
Because emergency breaking should just work, regardless of mode.