Hibiscus: It is most unlikely you are paying 20 times what your neighbor is paying.
Proposition 13, passed overwhelmingly in 1978, limited property taxes to 1% of value and no more than a 2% increase per year. It has been watered down over the years to allow the 1% to increase to about 1.2 or 1.25% in many areas by voter-approved bonded debt.
So your neighbor has likely had a 2% increase per year if he owned the same property in 1978. That is over 32 years so with compounding his tax has more than doubled, including the bonded debt portion. Prop 13 is indeed a boon to long-time owners and yes, some would call that unfair.
But CA is not starved for revenues due to Prop 13. Since it passed total property tax revenues are up by a factor of eight, due to assessed value increases, more property, more people, etc.
CA government spending has far outpaced the growth in population plus inflation. CA does not have a revenue problem. CA has a spending problem.