This is also extremely uncomfortable. Different firmwares use different commands so we would end up with maybe 300 commands and masks. Entering them by hand is much quicker and more flexible as every week some firmware also gets new commands but host does not know this and also does not know what your version exactly supports.
In practice you need maybe 20 commands regularly and it is easy to remember them if you do much manual stuff. For the most frequent manual control even has it's controls so that many users do not need them except for so special things like calibration and autoleveling, which also depends not only on firmware but also compile option and printer type.