Insightful thankyou : )Nobody on this thread probably has anything in their tanks that was collected at a depth of more than 5 meters... maybe just a few things. The vast majority are collected on one breath with a mask only. Lots of stuff is collected waist-deep water at low tide.
Deeper dives, specialized equipment and rebreathers are used for fish which are worth a whole lot more and even then, dives of 50 meters are not common and those fish can sometimes cost tens of thousands of dollars.