Lets say that's true.

Floor 1 was built to hold up 100+ floors.

Floor 50 was built to hod up 50+ floors.

The strike was in the 8x floor range.

how does a steel framed structure collapse, say, 20-30 floors below the impact, and become weakened all the way down to the ground floor so that it follows the clear uniform pattern of ejection from air pressure all the way down?

There's only one answer to this. It wouldn't have done that. The expectation was that if (and that's a big if) it was going to fall, it would fall into its weakened side, and the top would fall over and yes it might bring a few floors with it, but the bottom would generally be intact.

It's difficult to deny the lateral ejection of material that sent things blocks away. It's difficult to deny the explosive evidence.

Lets say that's true.

Floor 1 was built to hold up 100+ floors.

Floor 50 was built to hod up 50+ floors.

The strike was in the 8x floor range.

how does a steel framed structure collapse, say, 20-30 floors below the impact, and become weakened all the way down to the ground floor so that it follows the clear pattern of ejection from air pressure all the way down?

There's only one answer to this. It wouldn't have. The expectation was that if (and that's a big if) it was going to fall, it would fall into its weakened side, and the top would fall over and yes it might bring a few floors with it, but the bottom would generally be intact.

It's difficult to deny the lateral ejection of material that sent things blocks away. It's difficult to deny the explosive evidence.