The cries of doom come from speculators who only got into BTC to get rich then lost money with a downturn. The pessimism is encouraged by bankers and other opponents of BTC.
You see the same thing in the stock market. It's always the end of the world to speculators. What we have to remember is that speculators are basically gambling. They have no idea what they are doing. They read an article saying that X is going to the moon so they buy in without any real idea why, or they read an article on daytrading and think "I can do that" again without any real knowledge. So they gamble in, lose everything, and start to attack whatever caused them to lose money—because it can't be their fault, after all.
This is how it's always been and how it will always be. I've been trading in the stock market long enough to have seen this many many many times. What happens there, happens in the crypto markets too.
True believers in BTC or in a stock or whatever never react like this. Just ignore the noise. It is very healthy to occasionally shake out all the speculators.
BCH is total greed ridden and it wont take over bitcoin. You can see the flip flop of funds right now from BTC into BCH and now BCH to BTC because of the price increase its why its falling today. Also tomorrow spells major doom for BCH as it hard forks.