While monster cables are absolutely a joke of a product, there is different quality between cables. I have 3 different usb a to usb c 3.0 cables and they are all different. One of them charges so poorly my phone chucks a warning, one does about double standard speed and the 3rd one maxes out my phones fast charge.
Some usb3 cords just don't have any shielding at all. It's nearly always super dirt cheap ones, but you can still buy them if you don't know the difference.