Not all endtime religions teach that most humans will die.
The New Apostolic Church is a really interesting example. From what I can make out, they teach that Armageddon is very close, but that prior to the end there will be a huge influx of people into their church. I attended a service where the entire focus of the sermon was that members of the church should not resent all the new converts that will join their church before Armageddon. They apparently worry that some members will look down on newer converts as Armageddon approaches. They seem to believe that the end is near and that most of humanity will be saved in the end.