40gbps is an insane data rate that requires shielding, precision, and testing. There is no way you are getting that for $2. That said, outside of connecting a laptop to your monitor, you don't need a 40gbps cable.

The apple usb c charging cable is like $30, it is well worth the money of you are into software defined radio I can report. Not sure what magic they pulled of, but all the tricks in the book it seems!

okay, i mean, that's exactly what my original comment said: this is only a problem if you buy cheap cables.

I have some Thunderbolt cables that are like $80 apiece because they're like 3 meters long. I have like five or six of them because each one only carries one video signal.

(I used Thunderbolt so that touch and pen inputs could go over the one cable. These days though I just use a MacBook Pro, and hook up a capture card when I need to access the Windows)