Help with Trash trashbin_retention_obligation

Nextcloud version (eg, 18.0.2): 19.0.3
Operating system and version (eg, Ubuntu 20.04): Ubuntu 20.04
Apache or nginx version (eg, Apache 2.4.25): nginx/1.18.0
PHP version (eg, 7.1): 7.4.3

Hi. I’ve more a question than a support request. I’ve configured

  'trashbin_retention_obligation' => 'auto, 30',

and according to docs this should mean:

 keeps files and folders in the trash bin for D+ days, delete anytime if space needed (note: files may not be deleted if space is not needed)

I’m focusing on if space needed: yesterday I had 30GB worth of groupfolder trash and 10GB free on disk (out of ~650, that is less than 3%), but apparently NC wasn’t deleting trash files. I checked cron and it’s running fine.

Shouldn’t it be cleaning up stuff when so few space is available?

This is the disk status on the interface after cleanup