No, because the firmware is in some part written in a ROM inside the CPU (for security reason, at least the part that has to verify and load the rest of the fir

No, because the firmware is in some part written in a ROM inside the CPU (for security reason, at least the part that has to verify and load the rest of the firmware from the external flash memory), so there is no way to replace it or even disable it (if there is a way, you could see it as a potential backdoor, and also an attacker could disable the firmware and bypass secure boot for example)