I've noticed that often people who say they wouldn't want to live forever are those who have no long-term grandiose goals that they feel are personally achievable given enough time (e.g. become a billionaire, live on Mars, create the next Google, etc.).

I've heard that there is a big longevity community in the valley.

I'm with you; but I can imagine a few reasons why people might not take it. Some really religious types might feel that it's "playing God" or somehow interfering with "God's plan for the world." Some really eco-focused types might feel that it's immoral to live that long and therefore consume even more natural resources. Some conspiracy nuts would assume it was part of a government plan to do $SOMETHING. And some people might just assume there would be some sort of unforeseen consequences.

Still, I bet most people would take it, and pretty quick.

Stepping up one meta point, a lot of people aren't actually teling you what they want, they're just flashing various social signals. As you say, put the pill in their hands, and, well, don't leave any of your body parts between their hands and their mouths if you don't want a nice new red welt.

Yes, there are some who would not for real, but one wonders how even they would feel five years in.

Cognitive dissonance. You can either live knowing and regretting that you're going to die one day, of you can find reasons to believe it's not a bad thing. In time, you can come to actually prefer things this way.

Talk's cheap if you're not faced with such a choice.