Also while similar to the others the B(5) DHS exemption on FOIA requests states: "Protects the integrity of the deliberative or policy-making processes within the agency by exempting from mandatory disclosure opinion, conclusions, and recommendations included within inter-agency or intra-agency memoranda or letters.

Example of information the Department of Homeland Security may withhold using 5: Draft documents and recommendations or other documents that reflect the personal opinion of the author rather than official agency position."

https://www.dhs.gov/foia-exemptions

It also might be worth noting that the link provided in the Gab post links to the National Archives and on said page they state it was uploaded in 2016. They might have been updated since then, is there any way to check this?