Shutting off the SBS is more for the safety of the person working on the car. If the door is opened , key turned on or brake pedal pressed, the system can wake up and pressurize the braking system.

And, the SBS system has a backup battery in addition to the regular battery that runs the rest of the car.

The grease will be standard wheel bearing grease.

A check that any shop can do is unplug the wheel speed sensor, attach a AC volt meter and spin the wheel. Both front wheels should produce similar voltage if not, have a look at the lower / non existent of the two.

I'm not sure if the error will clear by it's self if the fault is fixed, at minimum it will remain in memory for XX drive cycles.

I don't know that I'd call the SBS dreaded, there is much emotional response flying around out there in the face of data and logic.