Yes, it should be added back. It's just meeting some technical difficulties right now.
Also, to be clear, it's just file sharing/network storage, we shouldn't have advertised a NAS. After all, SD cards can't do raid disaster recovery.
The version that fixes it is in the final stages of testing. They are 4.3.17 and 4.5.17.
But I don't think the E750 has been released with 4.5.x firmware.So it is 4.3.17. You can find it in BETA:
https://dl.gl-inet.com/router/e750/
How did you upgrade to 4.5?