macOS Tahoe SMB Changes Break Synology Time Machine Backups Silently

Users migrating to macOS Tahoe are reporting that Apple's default changes to SMB protocol handling have silently disabled Time Machine backups to network-attached storage, specifically Synology NAS devices. The disruption stems from stricter default security settings in Tahoe, requiring manual configuration adjustments on both the client Mac and the NAS server to re-establish reliable connections.