There are over 8 Billion people on this planet and growing every day, and only 21 million Bitcoin.
Discussion
but why does that entail price going up? why would someone want to pay more to acquire something they'll use to pay with? I think they call it a premium... what about bitcoin makes that premium worth paying and who decides what it is?
The law of supply and demand is as fundamental as the laws of physics.
If supply is fixed, and demand increases, price will increase, always.
But it's a mistake to even think about Bitcoin in terms of USD price.
If everyone starts transacting in Bitcoin, the legacy currencies become worthless, so in time the exchange rate becomes irrelevant.
What matters is what Bitcoin can buy.
If everyone is using Bitcoin, and the global population keeps growing, then the distribution of Bitcoin among the population gets thinner and thinner.
With each passing year it costs less and less Bitcoin to buy the same goods.
This is the opposite of the financial system that we have grown up in, where inflation is the norm and it costs more and more dollars to buy the same goods.
The problem is. how do you start trading enough bitcoin for goods and services for it to actually be demanded? it's no good if some country ranked 180/200 is using it for a few million $$ worth of transactions... something really has to be denoted in satoshi's otherwise, your just going to get new fiat currencies replacing the old ones.. how does btc emerge triumphant in the system that exists?

It happens when merchants would rather accept BTC than USD.
USD is accepted around the world because it has been trusted, but inflation is eroding that trust.
There won't be a sudden switch from USD to BTC. It will happen slowly and organically, as more and more merchants begin accepting BTC.
Look at how the USD supply was increased starting in 2020 and beyond.
This is why we have inflation today, not some nonsense about Putin invading Ukraine like the Biden administration would have you believe.
it be interest to see BTC merchant adoption over time - I know lots of people used to purchase goods from china using btc as it was quick and effective, but obviously they banned crypto transactions of any kind... What if they do get inflation back say down to around 3%, that the US manage to regain some shred of credibility.... could btc just die out, replaced by CBDC's - I get the case for them not to be used, but will normies?