I agree with you. Bitcoin is in the midst of its growth cycle. It took smart phones 10 years, the internet 20 years, and TV 50 years to reach saturation. When bitcoin reaches saturation, which will be in a number of years, the price will be more stable. For what its worth Gold still sees 100% price increases and 50% price drops and it has been in use for so many millennia. Bitcoin, having a set supply, is purely demand driven, and thus will always see more volitility than a fiat currency which has adjustable supply. However, Bitcoin's inflation will drop below USD's soon, so it will be a safer place to park money over the long term (in the same way as Gold).
While these successful technologies did take a lot of years to be successful and while I'm indeed extremely bullish on bitcoin long-term, I'd always like to take the realistic approach and say that bitcoin isn't really guaranteed to succeed.
Also, with bitcoin's scarcity and mining difficulty, these can only help to a certain extent. Bitcoin could be at 21 million mined right now but it would still be extremely volatile due to the buy and sell offers from people who panic and speculate.