When we talk of bitcoin supply, we look at it as 21 million bitcoin, and people wonder how that can serve the whole 7 billion population, but we forgot that there are smaller units of bitcoin, we have the mbtc, we have the ubtc and we have the satoshi, and i will like to talk on the satoshi which i believe needs to be expanded to really serve the current economy.
SATOSHI,
This is the smallest units of bitcoin, and 1 bitcoin is equals to 100,000,000 satoshis, which means that the total satoshi that we have is 2100 thrillion satoshis.
The total circulating money of the world according to According to the Bank for International Settlements is 80 trillion dollars, the lowest denomination of usd is cent and 100 cent equals 1 dollar, so we have 8000 trillion cent circulating as money in the world, if satoshi is to be pegged to 1 cent and to be used as global currency, you see why it is necessary to have it expanded, because circulating money of the world will be short of about 5900 trillion satoshis.
You have made some valid explanation and down to the last unit of bitcoin which a lot of people have misinterpreted that its going to be the one that is unlimited. However, you conclusion did not take into consideration two things,
1. You are attaching a definite value to one satoshi which is not. The value of a good is not on the the volume of currency but the real worth. There was a time in Zimbabwe where a pauper is a ''billionaire'' because of the currency crises in that part of the world. So in essence, if the currency is limited to that number of Satoshis, it then means they would only be more valuable in themselves.
2. The limit again is assuming the only crypto currency we have is bitcoin forgetting that there are other reputable and longstanding coins that can be used in place of bitcoin which then ultimately reduce the pressure on crypto and its limited units.