> something happened to the model in training (RLHF?) that forcefully degraded its reasoning performance

I've been seeing more people speculating like this and I don't understand why. What evidence do we have for RLHF degrading performance on a key metric like reasoning? Why would this be tolerated by model developers?

Can someone point to an example of an AI researcher saying "oops, RLHF forcefully degrades reasoning capabilities, oh well, nothing we can do"?

It strikes me as conspiracist reasoning, like "there's a car that runs on water but they won't sell it because it would destroy oil profits".