Bitcoin will die. Same with any other currency, if there's no one using it, there's no reason for it to exist.
With no one spending Bitcoins, there wouldn't be any transaction volume. With the no one trading on the market, Bitcoins will be worthless.
I agree bitcoin will be worthless if no one will use it and in the same time makinb bitcoin transactions.
Other cryptocurrency might be affected , In sure not all because some of the coins are not in the price of bitcoin . Like TBC (The billion coin) which many of us are knowned is as a ponzi coin. But I give it just as an example.