The folder /Tasker/configs/auto has many subfolders in it, each is a backup of Tasker's data from a different date and time.
I would like to clear this folder.
Is there a way to do it via the GUI, or can I simply manually use a File Explorer and delete the subfolders under this folder?
In Tasker you have the auto backup options under preferences/miscellaneous.
The backups are a complete backup of your Tasker data just like you would get from manually creating a backup.
(should I leave the latest subfolder there and not delete it?
or Tasker uses SQLite to store its data, and hence does not even need the latest subfolder there)
You can delete the backups as long as you are sure you won't want to revert to any of them.
As for Tasker it will store the configuration internally so doesn't need these backups.