What they're saying has been true so far. But that does not mean it will continue to be true. Some smart money backed Altavista and Betamax in the beginning, too, but in time the money moved toward the better products.
so when do you expect smart money move away from a useless object called "natural diamond" ?
Ummm...When the DeBeers company can no longer hide the fact that diamonds are plentiful. Diamonds are a shiny piece of glass and it's all in the marketing, as you know. There's been some evidence that young people are moving away from gold as an object that's given artificially high value. Someday, maybe diamonds, too. Or maybe not.
When do you expect Microsoft and IBM to show that mobile devices are unneeded in today's world, when we can all have our own personal computers?
The only question is, which of these boxes does crypto-currency fit into? I would argue there is too much wrong with Bitcoin, and too many problems that are being addressed/solved by other, better currencies, for Bitcoin to succeed in the long run. But most of the Bitcoin infrastructure that smart money has supported (wallets, apps, etc.) will not be wasted, since (with minor adjustments) much of it can be used with any other crypto.