Bitcoin will always remain Bitcoin: the first, the original, the best. Ethereum will remain Ethereum, it will never replace Bitcoin.
yes you right bitcoin will always be bitcoin and yes it is the first crypto currency in the digital world and as compare to bitcoin ethereum is like the newest crypto currency and it has nothing to compete with bitcoin because looking at the price of bitcoin it is the number#1, looking at the popularity of bitcoin it is the first and also some countries has legalize bitcoin which prove that bitcoin will remain number 1 for long time.
no one know about the future that what is going to happen to bitcoin or any other currency, but if we study bitcoin and some other good potential crypto currencies we come to the conclusion that bitcoin will remain as number one for a long long time, because still the community of bitcoin is more than any other crypto currency, and on other side the popularity of bitcoin is also increasing more than any other crypto currency.