Bitcoin was designed to be honest and sound money. In the way that gold once was. Contrary to the way fiat money is.
For now, the fundamentals are simple: supply side is fixed and known, and demand is speculation.
In the ideal case for bitcoin, over time, people will gradually use bitcoin more for actual commerce. As this adoption increases, liquidity increases, and price becomes less volatile. The speculation we have now is the necessary first step on that road, because it gives bitcoin a price (i.e. props it up) and gives it some liquidity.
People complaining that bitcoin is just for crime are slandering it.
People complaining that it has no intrinsic value don't understand that nothing in the world has intrinsic value, including gold. Intrinsic value is bad monetary theory derived from bad philosophy.