I do not believe that this is accurate. California Investor Owned Utilities (IOUs) have had their profit decoupled from revenue since 1981. [0]
The Federal Energy Regulatory Commission (FERC) allows for an equity rate of return on assets of approx 10% (9.3). [1]
As a result, California IOUs don't have an incentive to sell more power, but do have an economic incentive to build more assets. Asset construction is driven by growing peak demand. Or under-investment in O&M.
I believe there is a distinction between profits for "transmission" specifically and for electric utilities more broadly. The FERC ruling that you reference is for PG&E's transmission assets, i.e. high voltage lines and transformers and such. I assume that their retail electric business is regulated by CPUC and has a different profit/revenue/whatever arrangement.