Bitcoin has a finite supply and many coins have lost access, which means it will become more scarce than the original total supply of 21 million BTC. But that doesn't mean its price will increase indefinitely and without end, it would be a bit of an exaggeration to say that bitcoin price will increase forever.

Everything has a limit and Bitcoin is no exception, Bitcoin will gradually stabilize and the growth rate will also slow down when it reaches the limit. This process is still ongoing and we can easily see bitcoin's growth rate slowing down over time. We no longer see bitcoins giving 10,000% or 1,000% returns, and instead bitcoins returns are decreasing as it matures and gets bigger. Once it reaches a certain limit, it will also become more stable and less volatile like gold.