Bad News
Regulation is increasing and news of doubt and uncertainty are denting the Bitcoin market in the United States, China, and India (its primary markets). This fear and doubt naturally causes the price of Bitcoin to fall and the price of altcoins to fall with it. An extreme high in recent months generated a wave of emotional buy/sell activity that (as always) created an abnormal "bubble" in the price of Bitcoin.
The "Bubble" is really a "Wave"
A bubble pops and a dramatic, typically sharp, fall occurs to below market values and stays there. If you look closely at the rise of Bitcoin over time you can see that it follows a standard tangent of inflation with occasional outlying waves. I call them waves because the value will spike (upward parabola) then fall (downward parabola) then resume "normal" along the tangent.
Savvy investors ride the wave
Seeing it this way means that as long as Bitcoin is under $8000 USD its on sale. Simply using a ruler to follow the tangent suggests that a price around $8000 is the currently "normal" price for Bitcoin. Will it go above that? Probably yes. Could it fall lower? Possibly. Nonetheless a buy and hold strategy is still a good one.
What about alts?
Although alts often rise and fall when Bitcoin does, the ratio is not equivalent. Now is a great time to look into alternative crypto investments like Steem, ADA, and Monero while the market is down. These currencies have been rising overall regardless of Bitcoin's waves.
Disclaimer; I am not a financial advisor and cryptocurrency is a HIGH RISK investment. Do not invest more than you can afford to lose 100% of. The following is my observation and not financial advice. Past results are not a prediction of future performance.