The only thing I can think of is the imbalance of distribution of bitcoin , which gave a few people a lot of bitcoins , even through the scams and hacks, and that giving them a chance to manipulate the prices.
But that is comparable to the distribution of fiat money in which the top %10 have something like %90 of the worlds money. Scams and hacks can be problems but most of what we have seen with bitcoin have all been third party problems and generally not a fault of bitcoin itself.