iOS 16.0 beta 1 added a new UIImage initialiser for creating a system image that allows both a variable color amount and symbol configuration to be provided: +[UIImage systemImageNamed:variableValue:withConfiguration:]
In beta 1 I was able to use this just fine and could happily mix variable color with all the different render modes.
In beta 2 using this initialiser always results in monochrome rendering.
In beta 2, if I ask for multicolor I get monochrome. I don't get the new automatic render as images such as iphone.homebutton.radiowaves.left.and.right appear in monochrome, not hierarchical.