Sure. Good public policy would already have vaccine passports. And the recall probably blocked them.
And Newsom will probably look at it now and decide he’s better off supporting Biden’s vaccination plan than coming up with his own. He has the business connections. Not that hard to call them up and make sure the big ones are all on board. Probably happening now.
A lot of the big ones are on board already. The problem though is that it's tied to the office reopenings in large part. And they can't fully reopen until the mask mandates are dropped. Many of the larger companies also self-insure their insurance costs...it's in their interest to keep those numbers down.
The problem is getting the remainder. The odds are that the mandate will be struck down (though it's not as good of odds as the Rs complaining about it think).