ALDL was proprietary to GM kind of like apple and their connector tomfoolery. In 1990-something CARB probably didn't want to buy all the different diagnostic tools so they said if you want to drive in California your car needs OBD-II. Now, I can check and clear codes on any modern car with a $35 tool.
I've noticed if I take my glasses off I don't recognize anyone around me unless I'm with people I know. I bet I have superman powers going on or sm idk.