It is estimated that in excess of 24 million feet of previously legal parking space across the state of California are lost as a result of the 20 foot AB413 reduction (80 feet per intersection) with no requirement to mark or indicate in any way this restriction to park.  

While there has been significant support for a repeal in the San Francisco area it is important to note that this is a State wide measure and to encourage those across the entire state to support the repeal. While there isn't a readily available exact count of the number of intersections in the State, as a precise figure is not publicly documented, possibly due to the vastness of California and its complex road network, estimates suggest that California has millions of intersections across the state.  However a 2022 study from University of California, Berkeley academic Marcel Maron shows San Francisco has 6,399 intersections using Satellite-imagery based analysis. Let's assume a very conservative single parking spot loss per twenty foot loss which is clearly an underestimate as there are very few cars that are twenty foot long. Now, with four approach sides lost per intersection, (considers both ordinary two way streets where one approach side is lost and one way streets where both sides of the approach are lost to parking) so 80 feet per intersection, the loss in parking gives 25,596 twenty foot spaces or 511,920 feet for San Francisco. Here is the link to the study https://journals.sagepub.com/doi/10.1177/23998083221081530  From United States Census Bureau data California has a 38.97 million (2023) population and San Francisco 808,988 (2023) population.  Using population to scale the Satellite-imagery based analysis we obtain 24,659,849 feet loss in parking so, rounding, in excess of 24 million feet.