They will have issues but I think he's overstating that some. I seriously doubt Carter, Bolden and Bagley will be on the court together too much remember they still have Gary Trent Jr coming in a terrific shooter, they have Duval, and they return Grayson Allen who when he's not tripping people is a good shooter. O'Connell another freshman is supposed to be a very good shooter, not sure how much he'll actually play with Allen and Trent.
They should be really big, neither Carter nor Bolden are bigtime shot blockers, Bagley can be but he doesn't really want to play the post so who knows where they play him defensively. But they're going to be extremely long and should be a menace rebounding wise.
I think the biggest question will be playing time and finding the right lineups but that's always a nice problem.
Everyone has weaknesses, Kansas has a lack of depth due to having several transfers sitting out, especially their front line, UK as always inexperienced, Arizona the question is likely PG, Duke has some too.
I certainly don't think Bagley guarantees Duke an NC, I'm still not clear he'll actually play although it sounds much more likely based on what is being said now about his academics.