For now it has settled around $16k falling from $17k-$18k and has been there which is making people panic, and altcoins are rising for some days now. So, by the year 2018, the price will rise up again (mainly by January) above $20k, and I pray it does not affect the altcoins this time.
Altcoins will always get affected by what direction Bitcoin moves into, which should be clear by now after all the time we have seen it happen. It makes sense as well, because money moves from one place to another based on where people think they will be gaining the best possible profits. If you liquidated Bitcoin at near $20,000 levels, and took positions in the altcoin market, you have done exceptionally well. It's smart and logical thinking that allows you to utilize Bitcoin's volatility. If you have done it right, you have ended up with more Bitcoin quantity than before the correction from near $20,000 levels till where we stand right now.