Should an athlete intentionally sit at the bottom of a Snatch or try to stand immediately? In my opinion, the answer is not about the time spent under the bar, the answer has to do with stabilization.
I do not recommend an athlete pause on purpose (when there is no) or would I like them to rush to stand… which can cause failed attempts. I prefer the athlete stabilize first, then rise, no matter how long or short it takes. If an athlete needs a few extra seconds to control the overhead squat position, great. If they are confident enough and can sense they are able to rise without hesitation, go for it. Coaches should encourage stabilization  instead of  forcing a pause or quick rise.