Yes, the price dump comes first. The miners so called capitulation usually comes after that.
This idea originates from 2014.
True, but sometimes you can predict a higher or a lower demand. In the beginning of a bull market there will be a higher demand. There are rules how to recognize the start of a bull market. Bitcoin new bull trend market started in may this year. That's why there was a higher demand and more buying in april, may, june at the higher price rather than in december at 3200 USD. When bitcoin was worth 3200 USD, this was the best buy opportunity, yet almost nobody wanted to buy. There was a low demand for bitcoin near the bottom. After bitcoin reached 7k and 8k there was a higher demand, even if the buyer had to pay twice as much for 1 Bitcoin.