Enable BuddyPress Docs folders for all contexts (not just groups which is the default)

enable-global-folders-for-bpdocs.php

<?php 
// Enables folders for group, user, and global doc directories.
add_filter( 'bp_docs_enable_folders_for_current_context', '__return_true' );

// Shows the folder metabox on the doc edit screen.
add_filter( 'bp_docs_folders_force_metabox', '__return_true' );