Modern UI | Calendar feature parity - show more than two folders deep

The modern interface does not display calendar folder groups deeper than two layers. In the Classic UI you can see multiple deep. Users who have folder for the Department and then the Staff & Managers, and sub groups within the Staff folder are out of luck when needing to see the individual calendars within the group sub-folder of the Staff folder

And what’s with the tiny checkboxes for folders in Modern UI?