Now the question is, why in which way, this is good for ETH holders? I don't seem to understand this, why people getting excited by the chance that ETH can flip BTC?
Surely those excited people are traders.

Eth holders, or any other token holder, will be happy see his holdings
But for the long term run, i think it's not a realistic expectation as it's yet based on the charts made in a certain time. For the simple reason that Eth situation is more fluctuated than bitcoin by all terms.