Let's also take a closer look at this data by providing some context. It's one thing to look at PSU's raw roster data from 2012-2016 in a vacuum, but here it is in relation to that of Ohio State, Michigan and Michigan State:
Class rankings in B1G
Ohio State: 1st, 1st, 1st, 1st, 1st
Michigan: 2nd, 2nd, 2nd, 5th, 2nd
Michigan State: 5th, 5th, 4th, 3rd, 3rd
Penn State: 8th, 4th, 3rd, 2nd, 4th
And total scholarships over those five years...
Ohio State: 137
Michigan: 137
Michigan State: 106
Penn State: 110
That puts PSU an entire class behind OSU and UM.
Now let's take a look at just the 2012-2014 classes, kids who would be in their third to fifth year in the program, thus seemingly making up the backbone of the roster:
Ohio State: 86
Michigan: 95
Michigan State: 65
Penn State: 65
That's another sizable advantage for OSU and UM, and then consider we've already established that PSU's 2012 class was not very good and the 2013 class was very small and has few contributors left in the program.
Do things outside of the sanctions at PSU have to improve for the program to get back to the upper echelon of the conference? Yes. But the sanctions absolutely impacted the roster. Arguing otherwise is ridiculous.
So, accepting your position (that recruiting from 2012 and 2013 explains the difference), I'm sure that Penn State and Michigan State are two evenly matched programs during this coaching staff's tenure.
Again, there were no sanctions when the class of 2012 hit NSD. They had no effect on who was signed that year because they did not yet exist.