Riley in year 2 had a team full of experienced and quality multi year starters that Bo left behind. That had nothing to do with Mike Riley...
Comparatively, Frost in year 2 is stuck with a team full of Riley recruits as upper classmen who have no idea how to win, have terrible habits, and pretty much didn't have a strength program for the first 3 years of their career. Meanwhile, all the best players on the team, with exception of JD, are 1st or 2nd year players that Frost & co recruited.
So to break it down more simply, signs of regression vs signs of progression