Yes, I agree with you. That's what "whales" do every time. They manipulate small investors and take millions of profits. That's why people who can't hold long lose in cryptocurrency trading.
Even there are so many cryptocurrencies in the market, not a single one is near bitcoin so I think it at least for 10 more years bitcoin will remain number #1.
This is a hard time for all the cryptocurrencies. Not only ethereum, even bitcoin was so much dumped in past few weeks but I think it will recover soon.