Ok thanks both for the responses.
So there is still room for growth in retail investors
https://www.buybitcoinworldwide.com/how-many-bitcoin-users/ but there is still a max limit there
Modern websites say "In 2019, total world wealth grew by $9.1 trillion to $360.6 trillion"
https://www.visualcapitalist.com/the-88-trillion-world-economy-in-one-chart/So if 1% of all that went into btc that would be $3.6 trillion which makes btc go about 4 fold
and retail vs institutional investors looks around even
https://www.coindesk.com/bitcoin-retail-flows-jpmorganbtc will never be a world currency because of the slow tx time, high cost, and low tx per second (all modern cryptos are better than it) so its only function now for big businesses like tesla (yes they sell cars for btc but waiting 1 hour and paying 20 usd on a 100k transaction is not a big problem) and investment banks etc is the hope it goes up in the future.
So eventually buyers have to run out and it may be a lot sooner than 2140 when the last coin is mined.
For as long as there is fiat, a portion of it will always go to Bitcoin. And 1% is a little too low an estimation.
BTC will never be a world currency? Will? Never? It already is. Slow time? Try fiat, the clearing alone takes days. High cost? Try sending billions in BTC, your fee won't even reach a hundred dollars.
We'll see if buyers will drain out in the future. For me, it won't. For as long as power over money is monopolized by the few people inside central banks and governments, there will be buyers. For as long as money is controlled by human beings, there will be abuse, and there will be reasons to therefore buy Bitcoin.