It seemed like the idea was that they were living in a world of illusions where they could be and do anything they wanted, but it was ultimately meaningless and empty. the problem is that the author failed to really show this important latter part and they're portrayed as having lived it up in an endless party for thousands of years then getting their peaceful send-off with no real downsides. I know there's supposed to be a lot of Buddhist themes to the story so it felt like a massive missed opportunity to demonstrate the pitfalls of materialism. I really don't see how the main character wound up any better off than the remainder of the cast after a lifetime of getting the short end of the stick.