I've recently updated my Ender 3 Pro to the latest Marlin 2.0 firmware and when I press autohome or try to move the axis, I hear a very quiet noise from the motors trying to move and then they just don't. I did get an error message about EEPROM when I first booted the printer after flashing but I just pressed reset and the issue hasn't come back even after trying multiple different firmware versions.
This is theoretical assumption, but I suppose that your steps/mm values are now wrong in EEPROM - specifically they are set to 0 (zeroed steps per mm)? Could you please use LCD and navigate to Configuration > Advanced Settings > Steps per mm and check what values are set there? If there are zeros, could you set them to positive values (e.g. =80) and check homing again? Than you may save changes using Configuration > Store Settings.
I just made following test proving that this may be the cause. I set steps per mm for X=0 (executed G-Code:
M92 X0 from serial terminal) and tried to move X. The stepper motor was enabled (quiet noise or hiss), but it not moved at all. There was no additional feedback e.g. on LCD. Pretty similar.
If this is not the only broken setting, then option Configuration > Restore Defaults should reset EEPROM to values defined in Marlin's configuration. I needed to perform Configuration > Store Settings to make it persistent. But this will reset many other values, so I would suggest to write down all current values from LCD before doing the reset, for reference in future (in case they were valuable). And still you may not see all settins in LCD, therefore I would use g-code for this operation - see below.