I have a theory that the SQ42 Vertical Slice was cancelled due to Infinite Warfare showing them up.
Within two months they went from "nearly done" to contradicting themselves about the nature of what the demo would even be. There's a big thing that happened in those two months and it's the launch of Infinite Warfare. A blockbuster military scifi AAA dogfighting and on foot combat game that simulates downtime between missions in your spaceship carrier and lets you freely choose which missions to do across a whole Star System, and performance-captured Game of Thrones characters, i.e exactly what SQ42 is supposed to be. It even does the more open-freeform combat situations that SQ42 is supposed to with your character movement, hacking into bots to turn them to your side, calling in air support, using turrets, even hijacking mechs, all of which is more dynamic than Star Marine combat.
Despite backers insisting SC will be insanely polished, unlike those evil publisher games, they've never put out anything polished for anyone to judge this, and I genuinely think they can't, even their pitch videos passed off as progress are buggy messes. IW is actually insanely polished and good looking, it has probably the most stunning space vistas of any released game and faces that don't look like they're melting.
So I think they realised their grand showing was crap compared to games actually released and chickened out, Chris then turns up to the Anniversary show announcing they're redoing the Vanduul and all their ships because they're not fidelitous enough, so they're probably redoing everything to try and stay on the bleeding edge. They can't convince anyone with gameplay, so they have to do so with graphics.
