The situations have critical differences.
Nebraska's drawing card in the Big 12 was its unique style of play. As college football morphed to high speed throwing and exotic offenses, UNL was still a place for the power lifters. The NFL was never going to draft the Nebraska QB to play QB because he was going to be a strong runner who could occasionally throw the ball to an open TE or busted out WR. The play was almost always made by the massive corn fed dudes crushing the man in front of them.
When they abandoned that style, they were just another pro style set trying to bid for the services of pro style players. No real selling point.
Oklahoma had continuity. Stoops connected with a whole ton of brilliant coordinators and managed his staff accordingly. Full marks to him. I have my own opinion about Lincoln Riley's talent (I think Stoops left him "good enough" against a depleted Big 12, and now he's competing against air in the Pac), but he was supposed to keep the train on the tracks. Instead, he picked up the entire train and ran away - at the worst possible time, since players suddenly enjoyed practically unfettered mobility.
We'll have to see how Venables works out. I dunno why sportswriters want to make such preposterous excuses for last season. Going in, there was a high probability of disaster, and disaster occurred. Cramming together a bunch of transfer players didn't result in a team. Now, for 23-24, there's another influx of transfers, which surely will make it work this time? Maybe, but why?
Keep in mind, that's not Venables's fault. He's still trying to piece together an explosion that he didn't cause. He may yet turn out to be a great coach. He just wasn't able to pull off a miracle that no one had a right to expect.
