Bitcoin would be a very silly choice, but I can see value in some sort of cryptocoin. It would need to be firmly tied to something dependable, though.
Gold became a bad choice because the number of people expanded until a ounce of gold is currently worth over $3000, and that's an utterly silly coin. (It might be a reasonable investment, but that's gold itself, not gold futures. And then you've got to worry about it being stolen.)
I can see national cryptocurrencies being reasonable. I can imagine some sort of "stablecoin" being reasonable. (But who would you trust to run it? And for this purpose it would need to be tied to something other than a national currency.)
So the basic idea isn't totally bonkers. But using BitCoin is.