I've already acknowledged that.
But here's the thing: Most of his stats weren't that much worse in Big 12 action. He averaged 10 points per game last year--that's significantly lower. But this year, that would have made him the third highest scorer, .1 points per game behind Tanner, .2 ppg ahead of Hill. I'd say we could have used those 10 points per game. We might be on the bubble right now or even solidly in the tourney.
Here's the downside and it's pretty mild: Harkless averaged 1 fewer assists and 1 fewer rebounds last year. His free throw percentage was worse, too (though that can hardly be attributed to the conference he played in).
The upside? His three-point shooting was 4 percentage points higher last year. In the Big 12. His overall shooting percentage was a tick higher last year, too. So I don't see solid evidence that the conference made a huge difference. Even if all he did was match last year's output, we're a better team with him.
Anything else? Do you have it in you to acknowledge Harkless might have made the team better this year? That, even settling for his 2022 stats, we could have used those 10 points, those four rebounds and most importantly his defense and hard-nosed play?