This kind of rebuttal absolutely fails, because it simply doesn't address the point. You're taking the OP completely out of context. The OP is arguing against cryonics evidence in the context of having to dish out substantial money. The pro-cryonics LW community asserts that you must pay money if you believe in cryonics, since it's the only rational decision, or some such logic. In response, critics (such as the OP) contend that cryonics evidence isn't sufficient to justify paying money. This is totally different from asserting that you don't believe in cryonics or the possibility of cryonics out of context.

In your examples, you don't have to pay out of your wallet if you believe that 1) practical fusion power, 2) human mission to Mars, 3) substantial life extension exists. These examples are misleading.