That's a virtual structure in github, not a legal construct. Those organisations have owners (minimum 2), but if they collude and go rogue, they can do quite a lot of harm. (See also https://docs.github.com/en/organizations/managing-peoples-access-to-your-organization-with-roles/roles-in-an-organization).

A formally incorporated nonprofit organization has statutes, organs, supervisory boards and all that by which they must adhere, so once set up properly, the software would be fully protected from malicious intent on a legal level.