If Segwit is implemented then bitcoin price is going to go up and be stable at a certain level. People i think are parking their funds currently in altcoins because they are afraid of the upcoming fork. Once it's gone though, bitcoin's dominance will increase by at least 20% back to an acceptable level, perhaps even 30% if ETH bubble crashes.
If chain split occurs tthough hen obviously it's going to be bad for bitcoin's image, and this infightinig is definitely going to negatively impact bitcoin, and this is one of the only scenarios where bitcoin will drop alongside altcoins.
The one in the imagination of wishful thinkers dreaming of cheap coins.
Cheap altcoins? Likely. Cheap BTC? Prolly not.