A reviewer needs to know what asset is being used, what the post is trying to communicate, what version they are looking at, and what decision is expected. When those pieces are split across tools, teams get duplicate comments, stale feedback, unclear ownership, and last-minute changes.
The right amount of process depends on the team. A small brand may need one editor and one approver; a larger organization may have several stakeholders. The core requirement is the same: a visible path from draft to sign-off without bypassing the reviewed content.