Obfuscation
By breaking streams of data down to the packet level, and then distributing those packets across multiple tunnels, each running over separate ISP links, it is impossible to reconstruct a complete datastream by looking at a single ISP link.
Packets are encapsulated and encrypted to the latest standards, but even if a snooper found a way to decrypt them, they would only have a broken selection of datastreams with no discernible beginnings and endings.
This obfuscation is a security feature unique to fully aggregated connections, where the packets are essentially shuffled and dealt between transport links, as opposed to traditional SD-WAN connections, which maintain single data streams down individual links, even in the event of link failure.
Obfuscation is an extra tool in the armoury protecting the privacy of datastreams for businesses.