The EFR32MG12 and later devices (MG13, MG14) list EM2 sleep current in the datasheet with voltage scaling enabled. However, the default energy mode configuration for EM2 is voltage scaling disabled. To enable voltage scaling, select the "DefaultMode Peripherals" tab of the hwconf file and click on the EMU peripheral.
In the properties window, change the property "EM2/3 voltage scaling level" from "Fast wake-up" to "Low power".
Click the Save icon and then Generate and Build your project.
Note: A feature request has been logged to enable voltage scaling in EM2 mode for sleepy device types selected in AppBuilder.