The studies they're referencing show a very small increase at 43 weeks (42 completed, as mentioned above), however when I say small... I mean small. Still not really comparable to the risks of injury, complication and death that come with induction and elective cesarean section.
Following that, there is another ACTUALLY statistically relevant increase in rates at 44/45+ weeks. However, as I said earlier, there is no strong evidence to suggest that the increase in stillbirth risk at 44+ is actually due to dysmaturity... as dysmaturity was not found in all of those cases. It's thought that that stillbirth leap actually has more to do with the defects or other genetic problems that the baby was at risk for/died of that ALSO had a side effect of prolonging gestation. Very, very few women go that far. Very few.
The most common cause of "going overdue"? Having your dates wrong. ;) EDDs are based on a 28 day cycle with day 14 ovulation, going by the first day of your last menstrual period. Even if we take away all of the, "different bodies mature at different ages" argument and pretend for a moment that 100% of babies are finished growing at EXACTLY 255 days; we're left with the vast, vast majority of women who still have an inaccurate due date (even by as much as 2-3 weeks) due to varying cycle lengths.