Downloading large outputs using Get-IshPublicationOutputData is slow, is there anything I can do to speed it up

I am currently using Get-IshPublicationOutputData to download output from a bunch of publications. I use this with powershell's foreach-object -parallel, which executes jobs in parallel without waiting for the current item in the for loop to complete. This works quite well for outputs where are relatively small, less than 100MB. I can download 300+ distinct outputs in a couple of minutes.

However, we also have some outputs that are 1GB+, and when trying to download those outputs using Get-IshPublicationOutputData, it is painfully slow to the point of being unusable. Is there anything I can do to speed this up?