The medical form might help those who are clueless.
I don't deny that.
The statement that "it's my decision how to live my life" borders on sociopathy.
I understand your point. The issue of social reasonability vs. individual liberty has long been contentious with a lot of gray area. The problem is, since nearly all of us have some sort of ties to society, and any substantial action we take could in theory impact others, if we take the 'my rights end where your nose begins' doctrine very far, my rights end.
I'm fat. That might run up insurance company costs. What if someone wants to legislate food access and mandate I be thin? We already pay more because my wife smokes.
Sociopathy disregards the value and rights of others. I'm not talking about disregarding those; I'm saying sometimes people weigh individual vs. 'other' competing agendas and consider the individual case more compelling.
But if I drown on a dive, I may ruin the careers of the DM and the boat captain, and certainly traumatize my dive buddy and the entire boat full of people.
Since I framed the issue in terms of individual liberty vs. submission to societal dictate, and you framed it in terms of selfishness vs. social responsibility (apologies if I misrepresented your view), let me offer a hypothetical exercise to explore diver motivations.
Let's say things change and nobody requires a medical form or clearance, no matter what. On the other hand, they remain available in their current form, and all divers are made aware of them.
It would be fascinating to know what % of divers who dispute those who check all 'nos' would still go through the medical clearance form process.
I ask because at that point, it's no longer about submitting to the dictates of bureaucrats, but rather solely about the 2 factors left:
1.) Protecting yourself (if you think the process will give you useful new info. you couldn't get otherwise).
2.) Protecting that boat staff and other people from peripheral effects as you describe.
People who would get the form done anyway are acting on the motives you demonstrate concern about.