Indeed. And even when there's enough space, $ looks better than USD on pretty much every screen. The same will go for an SAT symbol compared to "SAT"...

mattcrv

SAT, USD - same length.
However, as a UI designer, I understand the need have a symbol taking up just one character. Not always there is a space for "SAT"

bitcoin

satsymbol.org | It’s time for a better symbol for sats.

SAT, USD - same length. 
However, as a UI designer, I understand the need have a symbol taking up just one character. Not always there is a space for "SAT" 