The limit for exporting a database backup from a sandbox environment to asset library is limited to 50 GB (80 GB) bacpac size.

That means about 900 GB of data in the database.

Our largest customer have about 2.5 TB. So, we're not ale to export the database for archiving (company shutdown) purposes.

Please do not discuss about cleaning up data. We already do that (2.5 TB in production, before exporting from sandbox environment we cleanup 1 TB of data and we're using most of the standard cleaning tools coming from Micrsofot.

The limit must be extended to at least 500 GB.