No, miners will not go obsolete after all 21 million bitcoins have been mined. Miners collect all the transaction fees of all the transactions in each block they mine. So miners will continue being paid even after the last bitcoin is mined.
No, miners will not go obsolete after all 21 million bitcoins have been mined. Miners collect all the transaction fees of all the transactions in each block they mine. So miners will continue being paid even after the last bitcoin is mined.