primitives benchmarks

[x-senpai-x]

If the purpose of benchmarks over here is to compare the difference between M31 (which requires x^5 or higher) and fields like Koalabear/BabyBear that could use cheaper sboxes like x^3. Shouldn't we be comparing x^3 on Koala/BabyBear vs x**5 on M31 instead of just comparing the overhead that x^5 or x^7 have instead of just doing x^3 all on M31?
I may be wrong but just want the clarification.
And I think BabyBear still requires x⁷ S-box, meanwhile KoalaBear can use x³ S-box