Likely a tcp windows size issue (for a single tcp session as the VM switch might introduce delay), Windows has a fairly low default tcpwindow size set by default.

Try iperf with 10 simultaneous sessions. If the total value looks better, increase the tcpwindows size on the Windows machine

I always ask when I interview ppl. If they have it they can explain it, if they have nothing it’s a minor flag that they might not be technically hands-on, something to follow up on.