Reasons to hate microcode updates: * They enable companies to ship broken CPU's and fix them later thus a CPU undergoes less testing (remember when software/games didn't have and worked fine without a day one patch?) * Theoretically a nation state actor could screw around with a CPU and have an internal microcode update to secure their own systems, or something else like that. * It is a black box (at least with intel) that is just another step of the war on general purpose computing- the tivoization of hardware.