Bitcoin's limited supply (ie. scarcity) is not the reason for bitcoin's success and the massive potential for growth it has, it is just the cherry on top. The real reason for bitcoins potential is the unique utility it provides as the only available decentralized currency that can work globally in the safest way possible.
If it were any other way then thousands of altcoins that have limited supply would have also succeeded, some of which should have surpassed bitcoin since they are much scarcer than bitcoin (eg. 42 coin that has a supply of 42 coins!).
Yes, that's right, bitcoin and altcoin have a limited supply. but the thing that makes bitcoin rare is the power of its popularity level that surpasses anything else. Since its inception, bitcoin is still considered trivial, and when 2017 made bitcoin the only coin that could not be matched. then from year to year, bitcoin is becoming increasingly popular and in demand by investors, so whales and miners focus on spending bitcoin. increase the price every certain period and make the parent of all the altcoin that exist.