Do you think that the current price of gold is related to its use as a facilitator of trade, or to its use as a means of preserving - or even increasing - value in an uncertain future?
The same applies to Bitcoin. Only that Bitcoin is indisputably better as a facilitator of trade, and might be better as a means of preserving - or even increasing - value in an uncertain future.
+1
The killer app for Bitcoin is not commerce. For most things we want to buy and sell, we can already do so almost instantaneously and worldwide, via legacy methods such as credit cards. The current fiat monetary system, as corrupt and unstable as it is, is mostly "good enough" for 99% of day-to-day transactions. Anything you want to buy, you can, with enough effort, by using state money. Bitcoin adoption might shave off a few percent in commission, or a few days in speed, versus credit cards and money transfers, but that's a quantitative, not qualitative, change.
Instead, the "private store of value" premium in Bitcoin is (and will continue to be) the driving force behind its price. Bitcoin is your digital gold and personal offshore bank, at no cost to you, and without leaving your house. That's Bitcoin's disruptive killer app: intangible, transportable, mathematically guaranteed, financial security and privacy. A service not available anywhere else, at any price.
Which means there is no meaningful upper limit on Bitcoin's valuation: if personal privacy continues to erode, if draconian asset taxes and capital controls become widespread, fear could drive every single penny in global savings to Bitcoin, and they would stay there with a velocity of zero. Indefinitely.
Total global wealth is approximately $150 Trillion.
Divide by 21 million.
That's the upper limit and current trend on the Bitcoin price. Completely independent of how much commerce is transacted in Bitcoins.
For more thoughts on this topic, replace the world "gold" by "bitcoin" in the following article:
How Can We Possibly Calculate the Future Value of Bitcoin?
And read this great blog post by BrightAnarchist (whom I believe is a member of this forum):
The *Real* Advantages of Bitcoin