The download being cached in RAM kind of makes sense, curl will do the same (up to a point) if the output stream is slower than the download itself. For a scripting language, I think it makes sense. Microsoft deciding to alias wget to Invoke-WebRequest does make for a rather annoying side effect, but perhaps it was to be expected as all of their aliases for GNU tools are poor replacements.

I tried to look into the whole Expand-Archive thing, but as of https://github.com/PowerShell/Microsoft.PowerShell.Archive/c... I can't even find the Expand-Archive cmdlet source code anymore. The archive files themselves seem to have "expand" be unimplemented. Unless they moved the expand command to another repo for some reason, it looks like the entire command will disappear at one point?

Still, it does look like Expand-Archive was using the plain old System.IO.Compression library for its file I/O, though, although there is a bit of pre-processing to validate paths existing and such, that may take a while.