this was instituted almost 2 years ago--it's just remanufactured outrage and California bashing, IMO (a lot of other municipalities nationwide have similar ordinances).
The target seems pretty clear: mobile fly-by-night repair shops. I have seen some crazy stuff in California, including the guys doing a transmission swap on the sidewalk outside of a rental condo of mine. Pretty ingenious, actually. They unbolted the subframe and lifted the chassis off of the ground--had it up in the air on some cut 2x4's... They managed the whole thing in about 6 hours.
I think it's a lot of hand wringing over nothing.