I think they were extremely scared of 4o at that point, and were scared it could trigger some horrible event. Documented cases of severe psychosis because of AI started to surface at that time.
Just imagine what would've happened if a major terrorist attack was a result of someone getting mentally ill from AI, without the safety filters recognizing the danger.
The robotic tone was probably from over-correcting the sycophantic tendencies of 4o.
I think they've brought back a "personality" of sorts to ChatGPT 5.x. I've caught it more than once explaining something to me and saying "In my personal opinion", or "I personally enjoy <thing> the most". Which is always jarring, it doesn't "personally" or "enjoy" anything. We could be discussing videogames and it tells me which games "it personally enjoys the most". Bizarre.
Just imagine what would've happened if a major terrorist attack was a result of someone getting mentally ill from AI, without the safety filters recognizing the danger.
The robotic tone was probably from over-correcting the sycophantic tendencies of 4o.