If this study helps a woman who wants a natural birth fend off a care provider who is pushing an early induction or c-section that isn't medically indicated, I'd say that's a good thing.
The article makes it clear that the study doesn't really indicate whether individual babies will be affected by early delivery. It's about looking at trends in large populations. So, I'm not sure how valuable it is to individual women in their personal decision making, other than in the scenario I mentioned above.
Also, the article doesn't say whether the babies studied were cases where a mother was induced or elective a c-section, or if they were all natural onset of labor, or some mixture of the two. Also, they assessed babies at one year, but it doesn't tell us if delays present at 1 year lead to delays beyond the 1-year mark.
I would say there is a lot more study that needs to be done in order to really understand the long-term impact of early delivery. But hey, it's a start.