NFL Connections #83, Answers
The full solution: all four groups and the 16 names, sorted from the easiest group to the trickiest.
Won exactly two Super Bowls as coach
Mike Shanahan, Jimmy Johnson, Bill Parcells, Tom Coughlin
Head coach in college and the NFL
Pete Carroll, Nick Saban, Jim Harbaugh, Urban Meyer
NFL players turned head coaches
Mike Vrabel, DeMeco Ryans, Dan Campbell, Antonio Pierce
Super Bowl-winning coaches (2020s)
Bruce Arians, Sean McVay, Andy Reid, Nick Sirianni