It is fixed that Bitcoin will not exceed 21 million. So even if the demand increases over time, Bitcoin will not exceed the limit, so its value will continue to increase. And this is why bitcoin has given more profit than anyone in the last 10 years.

It has even surpassed gold. That is why big companies like MicroStrategy and Tesla have called Bitcoin Digital Gold.
 source  (https://www.bloomberg.com/news/articles/2021-02-08/bitcoin-is-the-scarcest-asset-microstrategy-ceo-saylor-says)

Michael Saylor also says that Fiat money is a melting ice cube. Bitcoin is the fire proof vault

That's why he understood that investing in Bitcoin is safe and that its output will be profitable.