> you take an idea (death is bad) and make it about the character of the people supporting it

Well... the Fable of the Dragon-Tyrant is not actually just about the idea that death is bad. It's both about the idea that death is bad, and it presents a specific set of ideas about how we should respond to death being bad. There is an element of fallacy here, and I think people should be careful about how they critique this, but there is also an element of real substantive criticism. Some passages from The Dragon-Tyrant:

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> The next morning, a billion people woke up and realized that their turn to be sent to the dragon would come before the projectile would be completed. A tipping point was reached. Whereas before, active support for the anti-dragonist cause had been limited to a small group of visionaries, it now became the number one priority and concern on everybody’s mind.

It's important to start with the fact that many of the critiques against the anti-aging movement are not actually critiques against the concept of anti-aging, they are critiques of a very real argument that the anti-aging crowd makes that researching and pouring public resources into this project should be the number one greatest priority that we have right now.

Given that context, given that Bostrom is arguing that we should be focusing on aging first and foremost above everything else, it is reasonable to ask questions about whether or not anti-aging research is something that is likely to matter before the very-long-term for anyone other than a select few rich people (we don't have functioning health care right now, most people are not going to have access to anti-aging technology), and it is reasonable to ask whether it is ethical to abandon solvable problems today (and the people affected by them) in favor of problems that may take at best a huge amount of time to solve.

Nobody criticizes cancer research over this kind of stuff because cancer research doesn't say that it should be the dominating social concern of the entire world.

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Bostrom also writes:

> The king and his people will face some major challenges when they recover from their celebration. Their society has been so conditioned and deformed by the presence of the dragon that a frightening void now exists. They will have to work creatively, on both an individual and a societal level, to develop conditions that will keep lives flourishingly dynamic and meaningful beyond the accustomed three-score-years-and-ten. [...] We can leave, for now, the long-lived fable people to grapple with these new challenges, while we try to make some progress in our own adventure

Another criticism of the anti-aging movement is that they tend to hand-wave the significance of social change as a precondition to removing death, not something that can happen after the fact. I mentioned healthcare above; Bostrom is very cognizant of the lives that will be lost if aging is solved 5 years later than it could have been. He does not seem to be cognizant of the lives that would be lost if anti-aging technology is inaccessible for 5 additional years. His moral treats this like you flip a switch and suddenly millions of lives are saved as soon as the technology is invented.

And that's just a really simplistic way to look at the world; if you're trying to cure aging, it doesn't make sense to think of radical social change as a future problem. Overpopulation is not the biggest problem we face after curing aging, and I think it's a fair criticism that anti-aging advocates are sometimes dismissive of extremely relevant, current problems that are not only worth solving for their own sake but are worth solving because you can't kill the dragon until after you solve problems like health care, resource scarcity, and entrenched wealth/resource hording.

Again, not everyone needs to work on every problem. It's fine for Bostrom to go out and evangelize anti-aging research, and to advocate for more funding, and it's fine for scientists to work on it. These are generally less controversial ideas on average than people think. But the critique becomes different when Bostrom is arguing that this needs to be everyone's priority. At that point I do start questioning some of the motives, or at least I start questioning his perspective.

It is impossible for me to imagine a world with universal immortality that looks anything like the world we have today. And if all anyone does is advocate for universal immortality, without first advocating for universal rights, universal access to care/resources/housing, universal human dignity, political changes, market changes, changes to how we think about how finite resources like property are distributed to an immortal population... those are not afterthoughts, if you wait until after you solve aging to tackle those problems, then you will create a horrifying dystopia for the majority of the population.

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TLDR, Bostrom argues in the story for a complete redistribution of effort entirely towards anti-aging, which is worth criticizing on its own as out of touch with the reality of how society functions and how we make progress towards goals, and out of touch with the social/political problems that are going to get in the way of actually curing death, and also is advocating that we should accept higher current casualties/suffering and is advocating that we should ignore other problems (and even potentially introduce more of them) until after death is solved.

There are dangers of falling into ad-hominems and fallacies about that argument, but it is still worth criticizing.