No, that's just right-wing propaganda. The threshold of felony theft was raised to $950. Before and after that change, California had one of the lowest thresholds in the nation. In Texas, for example, the threshold is $2500. So crime in California can't be explained by the change.
Not sure if comparison to Texas is appropriate. Gun laws and property protection laws are very different there and act is a big deterrent for such crimes.
The difference is that in Texas and other states, misdemeanors are still prosecuted. In San Francisco, DA Boudin *did not*.