When it comes to the discussion about bitcoin supply, always have it in mind that it is limited to this total supply of 21 million and when everything is completely mined and in circulation, it will remain volatile and people will decide on the buying or selling rate for it, since it's a decentralized network, bitcoin cannot be affected by inflation unlike the USD that have always been printed out from time to time and this is one of the ways fiat encourages inflation and bitcoin doesn't because political leaders will always print the traditional currency in excess and inflate the economy through, unregulated policies, miners will depend on transaction fee for their own reward because there will be no more blocks to be mined or rewarded for.