You’re right that you need to expend bitcoin to trade it, but this is more a weakness than a strength. It gives you a banking system of sorts, in that you’re guaranteed someone will handle your transaction for money. This also means that if the value of bitcoin drops then nobody will be around to do the calculations required to do transactions, making it an inherent risk.
You can downvote it all you want, but the value of the transaction is directly tied to the value of Bitcoin. This makes it profitable on the way up, and an outright danger in the way down because it'll prohibit you from selling your bitcoin when the value crashes.
Like I said, invest all you want, there are plenty of money to be made still, but at least be aware of the risks.
Now, what that means for the price is nothing really. Speculation commodities (like Bitcoin and gold) go up and they go down without a whole lot of rhyme or reason. But the analogy to gold is valid.