Starting from version 7.1, we moved the renameCollection static checks from the coordinator (primary shard) to the router (SERVER-75357). In order to ensure that those checks would be performed in multiversion scenarios (mongos in v7.0 and mongod in more recent version), they need to be kept in the coordinator until v8.0 has branched out.

When 8.0 becomes LTS, the checks in the primary shard should be removed.