On v18 (e7082), the scraper setting SETTING_USE_DIRECTORY_NAMES appears to be honoured inconsistently. Some folders within the same source scan correctly, but others appear to ignore this setting entirely and are only searched by filename. This results in many items not added to the library. This occurs regardless of the scraper configured, and occurs after resetting source content type, clearing all items from the path, and rescanning. There does not appear to be anything in common to the path names that fail to be passed to the scrapers correctly.
Debug with an example: https://pastebin.com/nkSGMpab
Debug with an example: https://pastebin.com/nkSGMpab