There are a lot of alternatives to fusion energy and since energy production is a widely recognized societal issue, making individual bets on that is not an immediate matter of life and death on a personal level.
I agree with you, though, that a sufficiently high probability estimate on the workability of cryonics is necessary to rationally spend money on it.
However, if you give 1% chance for both fusion and cryonics to work, it could still make sense to bet on the latter but not on the first.
Don't read too much into my fusion analogy; you're right that cryonics is different than fusion.
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July Part 1