"Whatever happens, it seems that cryptos will return some real-world application."

I agree! But unfortunately, therein lies the problem. Take Ripple and XRP for example. I have no doubt that the crypto technology developed by Ripple will be sufficient enough for Ripple to carve out a sizable space for itself in trans-border transactions, such as its partnership with Moneygram, and others. But what about its coin, XRP? There is not a shred of reliable evidence to show that XRP adoption will ever follow, especially given that the Ripple technology can operate without XRP. So, Ripple does well, and its owners all get super-rich, but what about XRP holders? They could quite easily be left holding a bag of useless coins, with no real value, or at leave no value beyond its current level.

What investors need to realize that when they invest in crypto coins, they are only investing in the coins, and NOT in the companies behind them, and that is what really needs to be regulated. Imagine buying traditional shares in a company, but not really owning part of the company, or having any say into how the company operates. I really don't think such a company would have many shareholders.