2016 DeoreXT group set (8000) had a chainring with straight wide teeth as a kind of narrow wide alternative, but a mate has just got a new bike with the 2017 8000 groupset and the chainring now has more pointy teeth with alternating narrow and wide teeth.
Is this straight tooth thingy dead then? Did it fail? Have I misunderstood the whole thing?

The DCE profile has been updated to be a thick/thin style. Both work well, but I prefer the old tall profile – it runs noticeably smoother than any thick/thin rings I’ve used and chain retention seems to be similar. Both are currently available aftermarket, but the older style is no longer made so won’t be around forever…

Ok, so it works fine? Been offered a groupset by my LBS very cheap, but it is the 2016.

Yup.