Truenas core iscsi performance

I have a 4x striped mirror (8x 7200rpm HDDs) setup. Tnas Core has a reserved 10G port for iSCSI (a different subnet). My (Windows 11) PC also has a reserved 10G port for iSCSI. Using a file backed iSCSI volume, I copy a single large file (~1TB) from the iSCSI volume mounted on my PC to a local NVMe SSD with a speed between 100-200 MB/s (what I see on file explorer). I can easily reach 600MB/s using an SMB share, so it is not directly related to the storage layout or the network. What would be the problem here ? What should I check ?

I have a similar issue with SCALE.