Bitcoin gaining dominance is a good symbol for the bull run we can expect bitcoin to be back to previous prices once the price stabilises and prepare for next bull rally
Bitcoin dominance is been above 50% for last many months and that is why the altcoins are directly dependent on bitcoins. In such dominant bitcoin market, when ever bitcoin pump or dump, all other altcoins will have severe impact.
Bitcoin can easily regain dominance in future because we had sharp falls in the value of the coin years ago and the loss was recovered so this time again the loss in the value will recover. Just stay hopeful and think positively.