Can anybody explain the difference between the baseline and aligned_function cases? As the article states, they contain the exact same code, and the only difference appears to be that in one case, the function starts at C0 while in the other it starts at A0.

As both are 32-byte aligned, none of the uarch features mentioned in the article should be able to explain the difference. If anything, the baseline has the higher alignment (to 64 bytes), and yet the baseline is slower.