You missed two more things we do know.
1) Bronco recruited in the 50s and 60s. We have been beat by teams who we have significantly less in terms of recruiting talent. We hear the excuse of the talent not being there which may be the case when playing an SEC team but not a Utah State, east Carolina or a UMass. This is 100 percent on coaching.
2) The other thing we know is this program has not lost this many games against bad teams as this year's team.
Now what I don't know but do believe and not out of ignorance based on what I do for a living is in any leadership change switching from a structured disclinarian to a more lax casual leader often leads to initial excitement and even some short term gains in productivity with some carry over from the previous regime. Often this fades if the new leader lacks vision and clear expectations of that vision. Again, not speaking out of any inside knowledge on this just an observation from watching many leaders struggle with the same circumstance.