No matter one's take on generic USB type C cables even if you only used an Apple branded USB type C charging cable at least you'd be able to use the cable with other devices too.
I.e. it's always a lose situation to have the non-standard cable. Either a generic USB cable would be better or the Apple brand cable would be better for more than just your Apple device.
That being said USB C cables for phone charging aren't where people usually run into the USB C standard confusion anyways.
I think the biggest risk in USB-C, for me, it makes me really nervous when I buy a cable, and even then I'm not 100% confident. When I buy a lightning cable, I have no fears. And they're not even more expensive anymore. Some of those USB-C cables are just as expensive.