The change collection code currently parses the BSON object to make various decisions.

In the serverless, if the change collection mode is enabled, then every oplog entry will be inspected by the change collection. Examining every BSONified oplog entry might be expensive and could reduce the write performance. This ticket is about refactoring the change collection so we make such a decision by inspecting the oplogEntry IDL spec rather. It should be noted that at the time of filing this ticket, the change collection was in the development phase and no performance implications were known. This ticket is desirable but not mandatory. The priority of this ticket is also very low.