Sets DisableBandwidthThrottling = 1 under LanmanWorkstation\Parameters. The SMB client self-throttles to avoid saturating slow links — but on a fast home/office LAN (gigabit+, NAS, file server) that throttle just caps your transfer speed below the network's real capability. Disabling it lets large file copies to/from network shares run at full wire speed. No downside on a fast LAN. Reboot required. Reversible.
MaxTweaks applies this tweak with one click and snapshots your original setting first, so you can revert it cleanly at any time. A System Restore point is offered before batch changes, and every tweak links to its official source.
Get MaxTweaksOfficial documentation: https://learn.microsoft.com/en-us/windows-server/storage/file-server/smb-performance-tuning