Forget “100% hi-modulus aero-space carbon”. It’s not about high- or low-modulus, it’s about the right carbon in the right spot (or TRCinTRS™ as we mockingly call it).
Fact: stiffer carbon is more brittle. So it's great for stiffness (on the sides of the downtube) but bad for impact loads (for example around the headtube).
Hence the best lay-up is a blend. Open strategically places the ultra-high modulus (very stiff) carbon where they can, and tougher grades of carbon where they must. That’s how the frames are both light and durable.