As for the "Man if only we were 10-2" vs. "We're really a 6-6 team who got lucky, just be happy with 9-3", I'd say as with anything, there's nothing wrong with dreaming and wanting a little more doesn't mean you aren't happy with what you have. Imagine winning $100,000 in the lottery, you'd be stoked, but had you just gotten that 1 more number that was 1 digit off, you'd have won over a million. It's ok to be like, man I was thiiiiiis close to winning a million. And yeah, we had some luck this year, we had some statistically improbable clutch plays and performance in OT and single possession games, but let's all enjoy the season we had, it truly was one of the most amazing things any of us has witnessed as fans.
I also do think the "where would we be if we had just beat Minnesota" question is a fair one, and so I'll answer it in a historical context. Historically 10-2 teams from a major conference make the CFP a good 84% of the time, however, of those 16% who missed due to a 3 loss team being selected over them, they all had one thing in common and that's that they had no CFP end of season Top 25 win whereas 3 loss teams did (and in most cases 1 was on the road). As such, even if we were 10-2 with losses to only Oregon and PSU, I'd still project us to fall right outside the playoff, either 1st or 2nd team out. Beating PSU and losing to Minnesota though? I'd have us as a lock to make the CFP.