The good of society must prevail over the good of the individual - Benito Mussolini
A twist on reductio ad Hitlerum?
One man's liberty is another man's hedonism...
In liberal societies, social standards aren't set by one man. The cultural norms and traditions develop from the group. Certain members of the group may argue that something is hedonism, others may argue its not. Its up to the partisans of both sides to state their cases and sway opinion. Social conservatives will often hew to the older methods because, to their mind, they've worked so far.
You're confusing social stigmas with legal sanctions, they aint the same...
Legal sanctions can provide extra support for the social stigmas. That doesn't always happen, especially in the cases in which the stigma has already died in the culture, but the law is still there. People just ignore the law. A social conservative who wanted to uphold the legitimacy of a stigma can butress it with a law if they act early enough, but that law will be meaningless if they wait until its already widely abandoned by the culture.
As for the rest of that, why do people study science when they're free not to now? If anything, the social stigma is to mock nerds
You bring up an interesting facet with your mocking nerds point. After enough people see that hedonism is more fun than hard work, hedonism itself can become its own value. People still remember that there used to be stigmas against hedonism, so in reaction to the echoes of the old stigmas (and in hopes that those old stigmas don't return), they stigmatize those who adhere to the old ways. You're cool if you do drugs and lame if you like to work.
Some people will still pursue noble avenues because that's what they like to do or because they still believe in the older values. However, other promising people will abadon them because they're too hard or not as fun. We probably all know people who were smart or talented when they were younger only to be peer pressured down a dead end path. Those people needed more rigid standards to keep them on the beneficial path. Without them, they fell to the wayside.
A social conservative would thus argue against legalizing drugs in an effort to delegitimize their use and to make those who do use them appear to the impressionable to be criminals and low lifes. However, the criminalization strategy would have to be in concert with convincing people to believe their point of view.
You're trying to equate libertarianism with hedonism which you equate with cultural decay, where has this ever happened?
The combination of social freedom and the disavowal of the legitimacy of legal moral codes is a relatively new phenomenon beginning in the 60s. Enlightenment thinkers based their beliefs of liberty and representative government on the idea that there would been shared civic beliefs and a shared sense of civic duty. That's why some of the colonies were fashioned as "Commonwealths." The importance and sanctity of these rules were emphasized by imposing legal punishment on those who violated them.
The social conservative could argue that the US is in a state of decline. The average American is dumber, poorer, more in debt, and more likely to be in prison than ever before, and is losing its edge in the sciences and manufacturing.
The welfare state promotes this laziness you've identified, and libertarians generally oppose welfare states...
So do social conservatives. Social conservatives also support stigmas against accepting such services. However, implicit in social conservative's condemnation of the welfare state is a moral judgment- laziness is wrong and should not be supported. In a social conservative's perfect world, no one would be lazy.
The libertarian viewpoint doesn't require a moral judgment against laziness. Rather, it stands for the proposition that people can be as lazy as they want to be, just don't take my money from me to help insulate the lazy from the repercussions of their laziness.
The other viewpoint would be that of the Social Democrat, where they believe that society can't judge people for their actions (people should be free to do as they please) but it should force society to pay to insulate those who make bad decisions from the repercussions of their bad decisions (i.e., there should be a welfare state).