Any system generally works as long as there is a mutual trust towards that system. Money is not that old invention, it was originally invented to store your wealth and do trades more easy way.

Even still you can see people trading their old furnitures, lamps and decoration to bags of coffee and whatnot since they don't feel comfortable of asking money or for them getting few bills from their old furnitures would be boring or too much like business.

My grandparents were farmers, it was not uncommon to trade part of your crop to other useful assets with your neighbor. Same happens still in many parts of the world. They don't have so much understanding what money even is. You cannot eat money.

The biggest threat i see in cryptocurrencies is the same as in money. Too many people are holding the assets as their wealth and therefore there is not enough circulation for that currency to be efficient or even useful. Also they can easily stirr the markets if they want. Like poking with the stick to the ants' nest.

Purely from the trading point of view - I don't like how they have picked one or few cryptos what you use to trade/measure the value of all the other cryptos with in exchanges. What evidently follows is that when those few selected cryptos go up and down then all the other cryptos more or less will follow the trend (on longer average value) since you are forced to use those selected few cryptos for trading.

I would like to see exchanges where you can trade straight with any pair of cryptos you want and only the historic value (as a pinpoint to a current, real market value against other cryptos) would matter. Only then it is free competition between cryptos and only then the best ones would be the winners on the long run.