Prop 13 is brought up a lot but it never made any sense to me that it also applies to commercial real estate used for businesses. I can see an argument for single family homes (primary dwellings) but property that large corporations own ? It makes no sense.

It was created by and for homeowners, but businesses aren't going to pass up a gift like that. It's actually worse for commercial property - building are owned by separate single purpose corporations, and if you want to sell the building, you sell fractions of the ownership in the corporation over time so there's never a big enough change to trigger a tax reassessment.

Occams razor: it was never about the SFH owners...