Why is the Bitcoin price dropping so much this week?

My thoughts are that people are selling their Bitcoin (which fees and processing time are so high right now) to buy AltCoins for a cheaper price, lower fee and faster processing time. I believe the “whales” who own the majority of Bitcoin are dumping it to buy the AltCoins only to buy BTC again when the price drops. Possible market manipulation or just the gold rush to AltCoins. Also, a factor of the dropping Bitcoin price was that Coinbase on Tuesday released Bitcoin Cash (BCH) which in-turn skyrocket that coin’s price while they used Bitcoin to buy it.