Adding to the answer of @Whit3rd:
I think what OP is trying to ask is more how does it come, that absorption in the direct semicondutor is higher from qualitative reasons, but the formula tells us, that the derivative $d\alpha / d (h\nu)$ is lower for the case of direct band gap?
What one has to keep in mind is that these formulas are only valid for photon energies close to the bandgap energy. And close to the bandgap energy, indeed absorption coefficient of indirect semiconductor scales faster with energy, but only in a certain range. If we increase the photon energy even more, at some point direct transitions will also be allowed and the formula for the absorption coefficient will change.
Also being proportional does not automatically tells us whether it is higher or lower, so faster scaling does not contradicts qualitative arguments given by @Whit3rd.