so the powershell robocopy /purge is taking an equivalent time to remove-item via powershell. The assumption by me is this `*Extra Dir -1` means that the robocopy is removing the subdirectories, and the analyzing each file as `*Extra File` is just going one by one, which leads to the actual purging occuring at time of assessment in the execution (not like the analyze in Explorer and then major deletion), which averages 3.1 files/sec removed (includes analyze time).
testing with 1:1 file sizes for those file/sec returns