Altcoins have their own time that they do very well and that is after Bitcoin has gotten most profit due to the halving effect. It's better to buy Bitcoin before and after the halving as you'll sure of profits, after Bitcoin has had its share of the market then the altcoins will start pumping as traders take their profits and start pumping their favourite altcoins. Bitcoin isn't the only cryptocurrency that have grown the most but it's growing very well as investors are pumped.
We have other cryptocurrency that have done very well but we have more of altcoins that are giving losses as money is going out of the altcoins market into Bitcoin as everyone is accumulating Bitcoin for the bull market that is expected to come before and after the halving is completed. Bitcoin can be relied on but it isn't giving the most profits. Altcoins can give you more profits but can't be relied due to greed from the communist supporting the altcoin.