The question is why proprietary microcode that ships with your CPU is fine, but microcode patches released later are non-free? According to the FSF, you should

The question is why proprietary microcode that ships with your CPU is fine, but microcode patches released later are non-free? According to the FSF, you should never apply a vendor's microcode patch and instead you should buy a newer processor from them which will ship with the microcode patch already burned in. You can't even argue that it is a difference of being stored in ROM vs. RAM because the existence of patches means that microcode is upgradeable.