Jeremy B. White here writes for Politico that a side effect of the California tax returns-ballot bill, if it is not invalidated in court, would be to lower Republican turnout in the March 2020 primary. Because California has its primary for all office in March, and because the top-two system requires Republicans for Congress and partisan state office to place first or second in March, Republican turnout (without Trump on its presidential primary ballot) could be depressed, which in turn would damage Republicans running for Congress and state legislature. Thanks to Rick Hasen for the link.