Bitcoin as a concept of a decentralized time-energy currency is immortal. It's form may change, it's components may change, but it will always be here. It's like the story of the ship of Thesius: If you build a ship and all the original components are replaced over time to keep the ship seaworthy, does it become a different ship or is it still the same ship? Further If all the original components are saved and reassembled, say into a museum piece, while the other one is still around after all it's repairs, which one is the "real" ship of Theseus? Bitcoin will change, and over time all it's code may be replaced with more efficient edits as are needed. In that case, is it still Bitcoin even if it has no original code left? I would say as long as it performs the job of decentralized debasement-free incorruptible time-energy money it will still be Bitcoin even if all the code has gradually changed. In spirit and heart even if not in body any longer.