Good q. Crime could go down as incapacitation from being in jail, as you said. That's likely biggest channel. Also, deterrence knowing that there is some financial penalty or detention (if cannot pay) when they commit crime, especially for cases of automatic release. But there are costs (see below).

Some research highlights that crime reduction benefits of pretrial detention from those channels are offset against longer-term crime increases. Those are because of disruptions to jobs and public benefits, family and social strain, criminogenic nature of jails, and stress in general.

CA example of emergency bail orders were unique in that it resulted in automatic release (because of "zero dollar" bail) for many offenses and was not generally paired with monitoring or case mgmt because of COVID pandemic.