One of these nerdies from discord pointed (yup again) that AE2 covered cable recipe use 72 mB of SBR instead of 36 mB, and for the silicone rubber recipe it use 36 mB of SR instead of 72 mB, when SBR should be more efficient than silicon rubber and it is, but for the AE2 covered cable recipe it isn't

So, it changed between for some reason. I checked it in 1.12 modpack and they have the same issue