So is a computer. And an SPG. And a BCD. They are costly and unnecessary crutches, too.
My dad started diving when he was 14. He only ever dived double steel 72s, with no computer, no SPG, and no BCD. In a thick Farmer John wetsuit. He dived the north Florida black water rivers and caves and he dove to 200' in the Navy with that configuration. He has told me all those things are unnecessary.
So, what's your point?
I think that this whole "scuba" thing is a waste, unnecessary and isn't only a crutch, it is a wheelchair!!