How can EV3 Gyro sensor drift be handled?
There are two options that I can think of.


Do the "hardware" fix before every run of the robot to reboot the sensor along with the "software" fix to zero it.
Don't use the Angle reading at all. To calibrate the sensor, sample the rate (d/s) 10 times or so and take the average to get the "at rest" rate offset and store it in a variable. Subtract this variable from the rate returned by the sensor to get the actual rate. Integrate the rate over time to calculate the angle. (I haven't actually attempted this myself, but this is how you use, for example, the HiTechnic Gyro sensor since it does not provide an angle).