I haven't seen comments anywhere picking up on the clues Hickman is dropping, and only one comment from anyone old enough to remember Krakoa. I don't think any of this is secret, or spoilery. For those too young to have seen it, Krakoa is not new. It was introduced in the late 70's after X-Men had been cancelled for a few years and Marvel wanted to try a relaunch with new characters. It was a “mutant island” created by nuke testing. The original X-Men were lured there, tentacles stuck in them, and the island fed off them. Cyclops memory was altered and he was sent back thinking that he had escaped and had to form a new team for a rescue. He had really been sent back for more take out. Hence the Uncanny X-Men. In some way not adequately explained having Wolverine and Storm there (it’s not clear what Nightcrawler, Colossus, and Thunderbird were doing) allowed them all to escape from Krakoa.
Now, either Hickman has retconned Krakoa’s motives along with it’s origin, making it as ancient as Apocalypse, or there’s something more mysterious here than everyone suddenly giving up on Xavier’s dream of coexistence. What is Krakoa getting out of all this other than than the warm fuzzies? Why are they all acting like they’re on drugs and suddenly cooperating with one and other? Why are humans that haven’t been properly prepared not allowed through the gates?
What do we know? Kitty Pryde, precogs, and unprepared humans are not allowed on Krakoa proper. Krakoa is devious, has it's own self-interest, can monkey with mutant minds, and can feed off them. We've seen at least one mutant "sent to a deep place" where he will be aware but helpless (like the trapped original X-Men were). The mutants are all acting like pod-people and very focused on getting all mutants onto Krakoa. They've come up with a way of making even more mutants by resurrection, and are making it a priority to make more mutants the old fashioned way. The X-Men are now in opposition to the rest of the Marvel universe. And most importantly, the whole thing has a great big reset button. Looks very much like Secret Wars in broad outline.