A bigger section + Kurt Vonnegut = Tons of confusion. Chapter 5 is the longest chapter in the book, and Vonnegut does a good but kind of confusing job at tying Billy’s time jumps together, and also making them seem somewhat more random. For those interested, here is a SparkNotes summary of chapter 5, as it is too much for me to get into.
Vonnegut’s biggest theme is that of simple acceptance of things to come. Billy’s signature line is “So it goes,” that being similar to one in our own world, “It is what it is.” The Tralfamadorians, when questioned about how the universe comes to an end, simply accept that much is true, and don’t do anything to stop it, even though they easily could. These creatures are blinded by the “So it goes” mentality, and Vonnegut is warning us to not fall into the same trap through his book. Vonnegut also makes a subtle connection between the Tralfamadorians and the Nazis, and it goes like this:

Billy Pilgrim asked the Tralfamadorians why they chose to abduct him. They replied simply, stating “Why you? Why anybody?”
When the prisoners were being marched into the prison camp, one nameless soldier said something about one of the guards in english. He meant no harm by it, and neither did he know that this specific guard also knew english, and he got beat up for it. Whilst the guard was beating him up, the soldier asks “Why me?” to which the guard replies “Vy you? Vy anybody?”
I think Vonnegut’s choice in using this highlights his anti-war sentiment and the purpose for which he wrote the book. Alongside the statement by one of the aliens, in which they say, “I have studied 30 planets and read reports on 100 more, and only on Earth have I heard of free will,” it is clear that free will is what Vonnegut sees as necessary to the prevention of war. The Tralfalmadorians have never heard of it, and they have wars and are incapable of preventing their doom. The Nazis famously used propaganda to essentially lower the free will of the average citizen, and they warred until their unraveling. Vonnegut is saying, through these subtle truths, that the only way war will be ended is if everyone on the planet has free will.
Ok, after this chapter, I am really excited to see what comes up in the next chapters. This one was a doozy, but at least it only goes downhill from here.