Ah, so in this instance, the reviewer chose Reject and Edit, which invokes the Community user to also reject it, and then lets the rejector edit the post inline.
The Community user also rejecting it essentially just forces that edit to be rejected so that the rejector can apply the changes they wanted.
The same goes for Improve Edit. The community user will also Approve the edit, which then lets the reviewer apply their edits on top of that suggested edit.
But, as far as whether this was a good choice for that particular reviewer or not...