You don’t learn depth from a number. You learn it from watching someone do it cleanly. This is one of the cleanest constant-weight dives on film.
Two things to notice on a rewatch: the descent is monotonously calm, no kicking sprint and no strain, and the ascent is slower than the bubbles. That isn’t style. It’s Boyle’s law doing the work, and a diver who trusts it instead of fighting it.
For context, elite constant-weight dives now exceed 130m. Recreational training tops out far lower, and that gap is almost entirely protocol, not physiology. Watch the buddy and the safety divers, not just the line.