I will also do like that, buy some altcoins that keep them in the wallet for the next 5 years, will I become a billionaire? Who knows?

Nobody knows but if those coins that you'll buy are not so good then don't expect yourself that you're holding some good coins. Being with the same fate as bitcoin on its early stage.
I don't think that's going to happen again for some other altcoins.
There are so many altcoins in the market that you have to choose the right altcoin to hold within 5 years, unless you choose between the two top altcoins between ETH and BNB, although there is no guarantee but the two top altcoins are more worth holding for investment than other altcoins.