Bitcoin is mainly used for smuggling and money laundering at the moment. The biggest problem is there is no huge military power to defend it like USD does, so if it got taken away by force, hacked, and stolen, that's it, you lose it.
So far it is not debt based and therefore it cannot be QE like all other currency, and its only benefit over physical gold (not electronic or depository note based) is easy transportation. Physical gold still have law of physics as a protection against QE, to a certain extend.
I suspects that in the future blockchain would be used to replace physical money or slow multi day transaction, but our money would still be issued by nations and protected by military forces.