Code 2316 only reflects the number of incidents, not the utilization of the database itself. Once you get to 1M incidents in the database the question is what business value those ealier incidents have especially if those incidents are not being remediated automatically.
As for web archive or deleted files, once removed from the database there is no way to reimport them back into the database. Web Archive is typically used for legal use cases where you need a static incident set to present to legal council. As the Enforce dtabase is constantly being updated as remediation goes on the export is necessary.