I just don't think this is as simple as it seems to us typing at dry desks.
Yes, there are idiots in every aspect of life, but that doesn't mean that we should politicize or legislate every aspect of life. In the case of rescue at sea, we do it out of humanitarian necessity, out of a moral obligation to our fellow humans. We are morally obligated to help others in need, even if they are stupid. We've all been stupid on land and at sea. All of us.
Cost? The rescuers are not contractors employed per rescue. They are already on salary waiting, trained for the opportunity to lend assistance; it's why they enter the SAR line of work. The gear is already purchased and the staff is on call; other than fuel costs (a relative pittance) it's a misnomer to think that government rescuers incur extra costs for a mission. They only quote the "cost" to justify future budgets.
I agree that one needs to be properly trained for an endeavor. But if things go wrong, we all
desire assistance. I doubt that anyone would ever shrug and say "I was stupid, I deserve to die." Let's not fool ourselves, sitting in dry, safe, quiet accommodations. The sea always looks smaller and the wind less severe in a photo. Especially at my desk.
IMO, the government should not enact unenforceable laws nor should we neglect our fellow humans in need. Instead, perhaps we should as another poster recommended, admonish the newbie boaters to set aside the 'round the world sailing plans and learn the basic skills on a 14' day sailor.