I don’t understand what you mean when you say a swipe is not general, but I’d like to. If you mean it’s only applicable to very specific situations, I agree. Escape motions also only come up in specific situations.
The way I see it is that you would swipe, only in cases in which, with alternate picking, you’d have to change something to avoid hitting a string on your way back.
In other words, you just played a B string with a downstroke, and your next note would be on the G string, with an upstroke.
Within those parameters, your choices are to avoid the B string with an escape motion, or plow through the B string with a swipe.
The distance the pick travels doesn’t change much between these two scenarios. If anything, the swiped pick stroke is a little shorter. Of course it has the disadvantage or hitting the B string on the way.
I guess what I’m saying is that the distance a swipe travels might be a disadvantage, but not compared to an escape motion.
Of course, I’m talking about adjacent strings here.