I wondered this myself, but as far as I can determine, a quick turn where they would have to play immediately would simply never happen, you would always create the part so that the page turn does not need to be taken quickly, that is the justification. The V.S. then becomes a precautionary indicator that reminds the performer “there is another page, the piece doesn’t end here”, since the thick bar line that you normally find at the end of a piece doesn’t always appear where you might expect in commercial scoring. If you are paying a 100-piece orchestra and the lead trumpet thinks they are done and fails to turn the page and misses a solo entry, thereby screwing up your recording, it wastes money. Probably they aren’t going to mess it up, but if they are especially sleepy on one day, even if they are normally right on the ball, it can happen. The commercial train of thought seems to be to pretend that the weird one-off mistake can occur at any point and write indications defensively based upon that.
I only found out about this commercial meaning as the TA for an orchestration course where I had to grade the parts, and the example parts of the teacher had a V.S. indication with 4 bars rest at the beginning of the following page (same tempo, < 120bpm, etc). I knew something was off vs. the classical meaning since they had several seconds to take the page turn, pretty leisurely. This was basically confirmed by the commercial copyist manual “The Art of Music Copying” by Clinton Roemer, and I further confirmed this “commercial” meaning with the instructor.