Not really. The property quoted in the article was purchased in 1974 and California brought in strict limits on property tax increases in 1978. So the propert

Not really. The property quoted in the article was purchased in 1974 and California brought in strict limits on property tax increases in 1978. So the property taxes are probably trivial. The house acts as an investment with high returns and favorable tax status. They can sell it or take out a mortgage if they ever need money. Given that burning down the property to avoid a long eviction struggle isn't unheard of, the owner is perfectly rational to decide not to rent it out.