It doesn't get any better, does it?
Try watching at 4K and 25% speed. Suddenly you see why it looks worse in stills than in motion.
Still looking forward to seeing more though. Hoping what they've said is true about it being an early demo and the final product being better. If it's open world, covering the whole Halo ring, that could be brilliant.
Still suspect we could be waiting up to a year for a (visually) complete game though. As it is, RT is delayed until some time after launch. Can see this being like Sea of Thieves, where it receives a lukewarm reception on launch, but years later is regarded as being pretty good.