Usually, the whales first invest in BTC, pump it and at a certain level, take profits and move the money to the altcoins and then again get profits.
Right now, we are seeing the same transition where Bitcoin isn't moving much, but ETH is leading the rally. The bitcoin dominance is decreasing, and I think a big altcoins season is awaiting us. However, I do not say that convert your bitcoin to ETH or altcoins, but if you have extra fiat money, it is time to invest in some altcoins and make quick money. But in the long term, bitcoin is the only and safest investment.
It is clear that history is repeating itself and the transformation you speak of is happening, but the funny thing is that many people do not believe it and do not want it to happen. They just want bitcoin to be the only currency that grows but it doesn't matter what they want because the market doesn't care and moves according to their will.
Those who think bitcoin is the only coin to reach ATH will have to shut up after a while. Because altcoin season is inevitable, and i even bet that ETH will outperform bitcoin like in the last cycle.
Of course, in the long run, bitcoin is still the best and safest, but in this cycle, I believe there will be many altcoins that can outperform bitcoin in terms of returns.