The ShardingCatalogClient is an API designed to handle reads from the config server metadata. It can be used by the shards, routers, and the config server itself.

When shards or routers use the ShardingCatalogClient API, they will internally access a remote shard to communicate with the config server. The choice of read preference is crucial in this scenario as it determines which node of the config server replica set will receive the request.

On the other hand, when the config server uses the sharding catalog client, it does via the version installed in the ShardingCatalogManager. It uses a local version of the ShardingCatalogClient.

In cases where it does not need to make a remote call, such as when using the local catalog client, there is no need to perform checks to determine the read preference.

The goal of this ticket is to eliminate the read preference selection when the sharding catalog client is used in local mode, which is exclusive to the config server role.