@Beachcomber, I think those number are stale (2017 which really means 2016). All the major CA utilities, PG&E, SCE, and SDG&E have transitioned pretty much all customers to TOU. I have a feeling other big utilities have either done the same or are going to.
I did a deep analysis of all the utility rates in the OpenEI database, in 2020 and there appeared to be a significant number of TOU rates. Plus the biggest 20% of the utilities cover probably 60% of the US households.
My tricks were beyond the obvious EV charging - One of the biggest was moving the dishwasher from running after dinner to running after breakfast. Another was catching errant floor heating, especially in our guest room.