This sounds like a bad idea.

It does, but mostly for the same reasons that cryonics does. It's a violation of Common Sense and Sensibility. But given the beliefs that tocomment has (emphasis: not mine!) it is the wise decision for him to make. He has just bitten the bullet and actually followed through from his stated beliefs with (token verbal support of) the rational conclusion.

I think tocomment has his predictions about the future miscallibrated and has probably not accounted for his own cognitive failure modes but I suspect that people would judge him to be 'unwise' almost completely independently of whether or not they share his premised beliefs.

Basically, I think we (that is, humans) are likely to judge him as naive and foolish because he is actually acting as though his beliefs should relate to his pragmatic choices.

By way of some illustration:

• A mainstream 'retirement plan' is probably making the same 'putting all your eggs in one basket' mistake that tocomment makes. It is by no means certain that the structures and circumstances that make conventionally wise retirement plans will remain in place. There are perhaps other more fundamental actions that should be taken to ensure future safety and wellbeing than investing in superannuation. "Creating a stash of gold somewhere" may be a little trite but "develop the kind of social and political connections and develop the skills and resources that will allow you to survive into your later years even in the face of social upheaval" is something that makes sense and has applied across all cultures and times. Yet we aren't likely to look down our noses at people who don't divert significant resources away from their 401k and into that sort of future insurance.
• "Retirement Plans" essentially amount to saving up lots of money for use while you go through the process of physical and mental decline and then death. A plausible and sane person may actually have values such that a conventional retirement plan is a strictly irrational allocation of resources. That person is probably still going to be labelled foolish, unwise or naive despite the fact that he is acting entirely in his own best interests. ie. At worst he is weird, not stupid but will usually be lumped with the latter judgement.