The web page: https://docs.mongodb.com/manual/reference/command/serverStatus/
reports on database replication operations
Is that on the primary and the replicate? What database replication operations are there on the primary? Are opcountersRepl a superset of opcounters?
But then the same web page says:
These values will differ from the [opcounters values because of how MongoDB serializes operations during replication.
So is a logical operation (eg. delete a set of rows) counted once in in opcounters, but then counted once for each row if the operation is serialized into multiple single row deletes?