Ya, prefer not to have to try to keep up with changes in membership, who are all in organization. Issue seems to be if main folder doesn't have public access, the folder (and files) inside main folder are not accessible. Is that true?
I'll hairsplit a little on terminology in the interests of accuracy. Folders don't have access levels. You can create a sharing link to a folder and set an access level on it. Your options for access on that link. You have "People with the link" (public access, but can be password protected), "People in your company" (it requires that the user to a) log into Box and b) be a part of your organization), and "People in the folder" (only those who already have access to the folder/files - typically used as a shortcut for collaborators). Oh, I said four, right? The forth is "remove link". ;-)
So, without full details of your use case it sounds like me that you'd want to identify the folder, the contents of which you need to make available to others in your organization, and make a shared link with "People in your company". You can set this link at any level. (Does not have to be a parent folder.) Then anyone in your org can get to the folder and everything inside it. You can choose whether to allow them to download or not.
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