As far as I understand, the 4-minute time is taken from a log where Ocean compares the rendering time of the old and new workstations, all renders in 4K.Even if you are correct about Ocean spending 4 minutes per frame render in the past (I don't remember and am not obsessed about it enough to check), you are forgetting an eency-weency fact that he was rendering HD videos back then. Now everything is in 4K (as you even quoted yourself).
4 times more pixels to render and 4K videos to encode instead of HD makes 45-hour or longer sessions totally plausible if you are correct about HD videos taking about 10 hours![]()
You are right about one thing, the rendering time there is completely different, because it was just a part of a larger message. The point was that even a beginner would understand that Ocean was lying if they multiplied the rendering time of one frame by the number of renders in the animation (apparently, this was intended for people like me). Although, as far as I understand, doing that is also wrong. Then there was a bunch of technical information that I don't understand.
At the end, it said that the rendering time of 150 images is not the same as the rendering time of an animation consisting of 150 frames. As far as I understand, the difference here is that when an image is rendered, it is rendered completely. But when an animation is rendered, only the first frame is rendered completely, because the next frame is practically the same with minor changes, and only those changes are rendered in it. Therefore, if it took 10 hours to render 150 images, then the time for an animation of 150 frames will be several times less. Although, perhaps I misunderstood something.