Inconsistent error on mongos when renameCollection target already exists

When renaming a collection to a target that already exists (without specifying dropTarget) renameCollection will fail with the following:

• errmsg: "target namespace exists"
• code: 48
• codeName: "NamespaceExists"

This corresponds to a documented error code: NamespaceExists(48) (message: "target namespace exists").

On mongos, the command responds is more cryptic:

• errmsg: "Target collection %s exists but dropTarget is not set"
• code: 5807601
• codeName: "Location5807601"

This error code originates from checkShardedRenamePreconditions.

Is it intentional for these errors to be inconsistent?

Note: This was tested on 5.0.x, but I presume the inconsistency goes back to older server versions.