I agree with you, there will be a lot of bitcoin maximalists here who don't like that fact, but there's no denying that ethereum's profits will be bigger than bitcoin's these days. Bitcoin is getting bigger and safer, but that will also prevent bitcoin from generating huge profits as before. And it can be said that Ethereum is a perfect choice for those who want bigger profits while still being safer than other altcoins. I believe everyone realizes that, and many people are also quietly investing mostly in ETH instead of bitcoin, but many people don't want to say it.
I just think that its just matter of strategy honestly, thats why some people when investing in bitcoin are trying to gain as much investment as they can basically keep adding the investment towards bitcoin
since it needs to scale up in term of capital to increase the returns. unlike eth which still pretty much could rise quite high considering the fact that its value still relatively low compared with bitcoin.
regardless though, someone could just invest in both of them suiting their own preferences.
I just don't think someone are limited to just investing only in one.