No one can change and replace bitcoin, because bitcoin is the future of cryptocurrency.
I totally agree with you. It seems to me that Bitcoin is the most important coin in the world of cryptocurrency. Everybody trusts this coin.
Right now yeah. But you just need a big institute who decide to create his own coin, and there you go.
Bitcoin is not as eternal as everyone think here, it's just thoughout the history of the crypto market, Bitcoin always had the upper hand. If another currency, created by an institution recognized by the world that shows better performances than Bitcoin, and behind it a goal for its making, then BTC will simply be replaced.
Everyone trusted the subprime market before, and then 2007/2008 happened.
A few big companies are already on it, and it would be naive to think that the big institutions are not already in there. It's still a bit too soon to know who will be the new king right now, it wouldn't be too surprinsing if BTC continue to be at the top (for differents reasons, but still quite similar), but I would be even less surprised if something else replaces it.