When everyone is aiming to have a Bitcoin, Bitcoin will become expensive and maybe kept as a luxury item since its supply is finite while adoption is ever-growing so we might find ourselves not wanting to part with our ever-increasing asset and wanting to keep it for maximum possible profit. So I agree that it is possible that an altcoin will be the one used for daily transactions and Bitcoin will be kept in stash as we will find ourselves keeping it for more profit.
What do you mean by centralized altcoin? Perhaps, yes.
However, up to this point, I still hope that Bitcoin becomes a more widely adopted alternative payment than altcoins. By seeking solutions to Bitcoin's limitations, at least Bitcoin's existence is more reliable compared to most altcoins that are created solely for developer profits.
At the very least, blockchain technology can be used by many people as an experiment. Until now, the implementation of blockchain technology continues to grow, but at a slow pace. It seems that the presence of governments or official institutions has control over the slow adoption of blockchain and cryptocurrency.