Bitcoin is the first coin, ethereum is totally different project, with different purpose and bitcoin and ethereum are not competitors. We can compare them in terms of price, bitcoin is much more expensive than ethereum is and maybe that will stay like that for a long time, maybe ethereum can come closer, time will tell. There`s a lot of things going on on ethereum platform and nobody should underestimate that.
Bitcoin and Ethereum should not be compared, so I agreed with you. It is same as Gold and Diamond, they are not direct competitors. There will be no flippening between the Bitcoin and Ethereum, because there is no overlap between their usages in real life. They will grow further together and will simultaneously contribute to growth of crypto in general.