Even the bear time there will be exchange exist and make their business ongoing, until many people are using exchange i think they will continue to operate and give good services to make their investors keep on investing with them.
well, not a few exchanger companies die because they were attacked by hackers. well, this usually happens when they lose a lot of bitcoin, or the ETH they have. this can make the exchanger lose confidence and die. however, nowadays it is rare.
On hacking incidents then theres no doubt that this can lead up for an exchange to be dead when funds are being stolen but as said these scenarios are quite rare. Exchangers mostly turn out to be dead
is on where they do lack out of popularity or demand which causes for them not to sustain the expense and end up closing due for that reason.