The distance between the plane of the largest sprocket and the plane of the smallest sprocket in a Sora cassette is about 34 mm.
When the rear derailleur cable is untethered, the spring in the rear derailleur brings it outside of the plane of the smallest sprocket. This must be somewhat the case, since even when the chain is on the smallest sprocket, the cable must be a little bit taut.
Yet as you see in the image below, the cable-untethered position is several millimeters outside the smallest sprocket. This means that the cable must first have quite a bit of tension to bring the pulleys under the smallest sprocket, and the tension at the largest sprocket must increase by that initial tension.
Can a rear derailleur reach the largest sprocket if the cable is already quite taut on the smallest sprocket?
In other words, does the rear derailleur have a range of motion that exceeds that needed to move between the planes of the smallest and largest sprockets?