[klempner]

There is no such thing as a C to C cable that is "power only" or doesn't support PD, unless it is grossly spec incompliant.

The minimal spec C to C cable is USB 2 data and supports power delivery with currents up to 3 amps (i.e. 60 W at 20V 3A)

This is enough for most phones, and almost all of the exceptions use proprietary charging that isn't going to work on a C to C cable anyway.

The labeling issue of all these cheap shit cables is a serious problem, but it is a nonissue in the phone charging context.

[hedgehog]

I already have three kinds of C to C cables, some that will work with my laptop+monitor and some that won't, then some power-only ones for random accessories. We can no-true-Scotsman all day but so far type C hasn't simplified my life and as far as I can tell it won't in the near future. iPhones switching for me will just mean throwing out a decade of Lightning cables and buying USB-C cables.

[klempner]

Are these "power only" C to C cables something you're explicitly going out and buying or something that comes with these random accessories?

[hedgehog]

They are charge cables that come with random accessories, I think I bought some long ones as well. Also A to C cables. As long as they're only used for low-draw devices it should be safe but requires keeping track.

[klempner]

The vast majority of C to C "charge" cables are USB 2 cables. I don't believe I have ever received or even seen a "charge only" non-captive C to C cable. A to C cables are a lot more common.

Do you have reason to believe that the C to C cables you got/bought don't support USB 2?

It doesn't make sense for a random accessory to come with a charge only C to C cable because USB 2 C to C cables are a dime a dozen. They're almost certainly paying more money to produce a spec violating cable.

[hedgehog]

They could have data support, I've never actually checked. The wires are pretty thin so I only trust them for charging the lights they came with. I have a bundle of similar looking A to mini or micro B cables of which I know many are charge-only. As long as they're super short I only rely on them being useful for charging.

[klempner]

In that case they almost certainly do have data support.

Keep in mind that power dissipation scales with the square of the current. That means that, as a first order approximation, relative to household 15 amp wiring, a 3 amp cable can be 1/25 of the size. You can get away with really thin wires for that.

The reason why you end up with thick USB C cables is because of either 5 amp support (requiring 2.8x bigger wires) and/or USB 3 support (requiring a bunch of extra higher spec wires). It is quite normal for plain old 3 amp USB 2 USB C cables to be thin.