I would think any one of NIMBY incumbents, rent control, and (CA-specific, obv) Prop 13/19 would individually do a lot more to artificially pump up rent prices than rent setting software.
Prop 13 drives down prices the same way mortgage interest drive down sales prices. low tax on homes purchased 30 years ago means higher taxes on new purchases.
New home buyers usually care about their monthly payment. high mortgage rates mean they can afford lower sales prices. High tax rates mean they can afford lower sales prices.
