DW:
(and indeed a design change to the 757) over the years,
What design change? Are you still hung up with your misinformation that the Birgenair Capt didn't have an AIR DATA: NORM/ALT switch on the panel in front of his left knee? That switch was there from the beginning of production of the 757/767.
The Capt. cocked up, that's all. DW, why are you trying to blame the 757, and let the A330 off free?
As for CB, thousands or millions of flights have successfully negotiated the ICTZ at flight levels since the day of the 707, with Wx radars far more primitive than what AF447 had, yet how many crashed?