What are some negative aspects of bitcoin? What features does it not have? What would be potential causes of it crashing? What would/does stand in its way of dominating fiat currency with its superior value proposition?

Since over half of all bitcoins that will be mined have already been mined, bitcoin only has an inflationary threat of about 40% (which is high but will take a lot of time and occurs at a decelerating rate). Since the supply is so limited, the value nearly goes up one-to-one with the amount of money that is put into the system. At the moment there is over 10 billion USD worth of bitcoins in circulation; so if this went up to 100 billion then each BTC would be about 10 time more valuable. What are some obstacles that could stop this from happening?