In this example we install debian 10 with --variant=minbase which gives us a minimal/tiny install. Don't use variant if you want the full size install.
mkdir /tmp/deb10files
debootstrap --variant=minbase buster /tmp/deb10files/
Did you get an error?
debootstrap --variant=minbase buster /home/theuser/VMs/deb10files/
You'll get this error if you make a directory in your home........
I've encountered this problem before and I believe it may affect other drivers (I could test but I don't have time). This was happening on my custom Linux system with the pcnet32 driver.
pcnet32: eth0: transmit timed out, status 97fb, resetting (and some other kernel module tracing in dmesg)
Basically it means the card is connected (it shows connected in full duplex etc.. and recognized if the cable is disconnected too) but no packets can be sent or received........