Old story but OBS vendor are doing more to accommodate legacy file protocols
Well, the potential use cases of OBS include working as backend storage to NAS heads (Cloudian HyperFile) for SMB and NFS file access. They might not be as fast as NAS filers but fast enough for most NAS use cases. Virtually every OBS vendor supports SMB and NFS file access methods today and some have supported them for years. Various NFS and SMB gateways and caching appliances have also been around for years (Panzura) that can handle file locking and manage a global namespace. OBS vendors like Caringo, Cloudian, Scality, and SwiftStack are improving their support for legacy file access methods which is to be expected because not every application has been re-written to use a RESTful API to access an object store. That said, every OBS vendor supports the AWS S3 API which is the most popular RESTful API used to access cloud storage. OBS is not about object storage per se, it is about supporting the hundreds of data access, data storage, data analytics, and data management solutions that can use OBS.