As of November 2020 a limit has been placed on the amount of data that can be download in one go.

Downloads of multiple assets require that the assets are compressed into a .zip file. With this change, no more than 20GB worth of assets can be zipped in one go. To download more than 20GB of data the download will need to be separated into small parts less than 20GB in size.

This limit does not apply to individual assets larger than 20GB, only the download of multiple assets.