I looked at the bolded statement recently and looked at all of our opponents offensive efficiency rating over the last 3 years. I used SP+ advanced stats, ESPN FPI advanced stats, and then looked at opponent adjusted PPA/EPA which is very important for looking at how units performed.
SP+ Opponent adjusted offensive efficiency ratings supported your thoughts.. National average in parentheses:
2021- 28.65 (28.64)
2022- 27.77 (27.67)
2023- 26.98 (25.86)
ESPN FPI Opponent adjusted offensive efficiency ratings didn’t agree with your thoughts, they actually think 2023 was the hardest we faced.. National average in parentheses:
2021 - 56.67 (49.14)
2022- 59.56 (48.99)
2023- 62.74 (49.69)
So SP+ thinks last year was the worst out of the 3 when averaging offenses efficiency ratings that we faced. ESPN FPI though thinks the opposite and they think 2023 was the toughest.
Both of those ratings are built off a number of different stats and analyses and they both will weight things differently, so not too surprising they are different, but one thing that is the backbone of a lot of advanced stats in football is Predicted Points Added (PPA)/Expected Points Added (EPA). This looks at every play an offense/defense/special teams has for the year and adds a point value for success or not success plus some other factors. If you look at opponent adjusted PPA of the offenses we have faced the last 3 years:
2021- .216 (.201)
2022- .208 (.177)
2023- .212 (.179)
So, PPA would have his first year as the toughest, then 2023, then 2022. In the end it depends on what service you want to use to support whatever argument when it comes to SP+ and ESPN FPI.. but PPA/EPA is the very close to the same formula no matter who does it so I look at that one a little more heavily personally. JMO.
This wasn’t meant to say you are wrong or right, everyone can make their own hypothesis based off the stats and what they think they saw over the year and at least one of the advanced stats agrees with you, I just wanted to provide some numbers for anyone interested for the bolded statement in your post.