it depends what your objectives are.
if you're simply looking for quadricep hypertrophy, you definitely do not need to go super low. you don't even need to need to bring your hip bone in line with the top of your knee at the bottom of the motion.
but when you go low, you get much more glute, abdominal, calf, and lower back activation .
that being said, i generally always bounce out of the bottom of squats, but it isn'tm an exaggerrated bounce, and i stay tight throughout the entire movement.
also, remember that everyone online can bench double weight, squat 2.5 body weight, and deadlift triple body weight.
funny, i've been training for 7 years in tons of gyms, and i never saw so many people that strong until i came online.