Yes, by default in samba, files created by the guest user are created under the account specified in configuration under "guest account", by default user "nobody". Creating them under the rights of the owner of the directory is introducing security risks that are not appropriate for a default configuration, in addition to diverging from upstream defaults. The use case of a totally unauthenticated writable share where files are created under an existing account is valid, but not for a default configuration. Setting "guest account = fabio" or "inherit owner" in the configuration file seems appropriate in that case.
Yes, by default in samba, files created by the guest user are created under the account specified in configuration under "guest account", by default user "nobody". Creating them under the rights of the owner of the directory is introducing security risks that are not appropriate for a default configuration, in addition to diverging from upstream defaults. The use case of a totally unauthenticated writable share where files are created under an existing account is valid, but not for a default configuration. Setting "guest account = fabio" or "inherit owner" in the configuration file seems appropriate in that case.