Except that running "ls" doesn't show you the directory content size, and "ncdu" requires the user to make a tea first. The above poster is right in saying that having this built-in to the filesystem metrics would be a huge win.
use a cronjob for `duc index`, then you can use `duc ui` to see the index. it doesn’t immediately update on change so it’s not quite what you’re looking for, but it might be the closest thing.