Now kindly suggest some altcoins those have potential enough to grow 40x to 50x within 4/5 years and Kindly explain your logic for supporting those.
People are always mentioning Ethereum just because of what they have seen so far, every four to five years we are always going to see Ethereum increase in value alongside Bitcoin and few other top cryptocurrencies in the market. There is always a chance for it to reach a new all time high price.
Another one that I will recommend, since you said nobody should talk about Ethereum and BNB is Polkadot; there is every possibility that it will increase more than the current value in the next four to five years. I don’t know if Solana will continue at this rate to move up in the next few years to come, if it will, then it is sure going to be a good bet. Next one I think will increase in the next four years is Terra, you should check it out as well.