Is pick slanting really needed to sweep?

From what I can tell, watching Troy Grady’s videos, pick slanting is needed for 'string hopping" I’m not sure if it is needed for an “upsweep” I may be incorrect on this. I think the pick slanting is to “free up” the pick from being caught in between the strings, and hitting the next string. If that makes sense. in a sweep, you want to 'hit the next string".