Earlier quoted context omitted.
Yes, by design! The most traditional way of deciding index weights is by market capitalization: if the world has thus far allocated more to Bitcoin than Ethereum, the index will too. Besides concurring with past "wisdom", this method minimizes management overhead. If Ethereum doubles in price tomorrow, so that by market capitalization it should have similar weight to Bitcoin, the index will already be "in position" b…
I hadn't considered this, why do you ever need to rebalance then?
The other cause of rebalance will be if they add members to the index, which would also upset all the ratios.