Don't know the original of the drawing or any relation to bearing seat angle.
I pulled it off the web to illustrate the difference between BB86...what the OP has and BB30 in terms of geometry.
I also dismiss the reference on the drawing that BB86 is 1.3 X's stronger. I almost pshopped that off the drawing because it wasn't my intent to highlight any strength difference. Would love to see the math on that aka moment of inertia calculation. More than a few 1500+ watt riders doing just fine on BB/PF30.