Yes $50,000 will be reached in 2018 based on simple economics. The recent dip is likely the lowest we will see bitcoin at ever again. While transactions times are slow and transfers expensive bitcoin has proven itself to be a store of value. Its use case was demonstrated in Zimbabwe, this year, where hyperinflation caused a flight to bitcoin.

That being said, if you're looking for the type of returns that bitcoin owners have seen the past 9 years, then you'll need to look to other coins, of which there are many that will go up exponentially in value over the coming years.