Where did you find that 4.5 is a better model? Everything from the video told me that 4.5 was largely a mistake and 4.1 beats 4.5 at everything. There's no point keeping 4.5 at this point.

Bigger numbers are supposed to mean better. 3.5, 4, 4.5. Going from 4 to 4.5 to 4.1 seems weird to most people. If it's better, it should of been GPT-4.6 or 5.0 or something else, not a downgraded number.