its not better technology that will replace bitcoin its better propaganda and consumer confidence keepers, some improvment i can see implemented in SC adjusting the fixed supply to a constant 3% economic growth stimulates (because economists think moderate monetary growth is good)  increasing the tx fees, we need more miners for security, and teh proponents saying you the people, listen up, we have embraced bitcoin's blockchain technology its been improved and is safe for consumer adoption, were moving our national currency into the blockchain.

and in the blink of an eye Bitcoins tiny billion dollar market cap is absorbed and assimilated and usurped. Replaced  not by better tech but by confidence spinning.