I do not totally agree with this statement mate, yes, all altcoins depend on BTC but altcoins price do not necessarily increase only when BTC price increases. Point of correction here, altcoins do better when BTC consolidates or moves sideways in a given range. Massive price increase or massive dump for BTC usually cause massive price dump for altcoins. This is the true correlation, but not a must in all cases and not otherwise.
That can also affect what has happened to the price of bitcoin because I am not sure altcoin will completely go up without the existing trend towards bitcoin, therefore altcoin will be more powerful when the pumping occurs simultaneously and when it ends it is even worse dump could occur.
Altcoins too make great name in the market. It is just that it is mostly get affected by the bitcoin market price movement. Whenever bitcoin market goes up or down altcoins will get affected as well.