Bitcoin's bullish run do affects other altcoins and in the past when bitcoin is getting pump almost all the altcoins will follow in the same direction and when it is getting dump the samething do happen . However,  now some of the altcoins has gone down to far that it will be difficult for them to recover.  Some altcoins are going to die and that means the next bull run may not affect them and it means if we have opportunity to sell those coins it is important we sell them now.