Honestly, I think the cluster of tech-savvy, young, smart-but-nonconformist types is really winning at the goal of being productive while happy. Not everybody makes it; but I've seen a lot of people have lives more satisfying than their parents ever could. People who've broken the conventional wisdom that you have to put up with a lot of bullshit because "that's life." Mainly, because instead of asking "What is the Thing To Do?" they've got the hang of asking "What is the best thing I could be doing?"

If cryonics is a bust, I'll grant that it's a genuine waste of money. The same is true for SIAI. (Though I'll mention that lots of otherwise fulfilled people donate to demonstrably inefficient charities that spend most of their money on employee salaries. Most middle-class people throw some money down the toilet and don't even notice it.) The other issues are not such a big deal. Leaving religious communities is not a blow to people who have figured out how to optimize life, because they aren't isolated any more. I don't even know if overuse of stimulants is that widespread -- I certainly know they aren't good for me.

As for having self-gratifying beliefs that aren't of much use ... well, everybody does that a little. Guilty as charged. But for me at least, LessWrong's favorite issues led me to interests in similar-but-not-identical issues. General AI is pretty opaque to me, but now I'm interested in narrow AI (and its statistical/mathematical cousins.) The abstract discussion of rationality has led me to take psychology and motivational advice more seriously.

Are LessWrong memes pretty confined to a subset of tech geeks and some young scientists and professionals? Yeah. For the moment, so what? That's the environment I want to be in; those are my friends, collaborators, and role models. Not everybody is suited to be a world-wide evangelist with a big bullhorn; I'm satisfied that there will always be people in the world who disagree with me.