I won a USBC to USBC lead not long ago, and put in my pd USBC charger.
My galaxy S8 was approximately 19%.
Using my new USBC/a lead, Vs the USBC/c lead, ....
The USBC/a lead was giving a time a couple mins quicker than the STANDARD USBC/c lead.
HOWEVER, both times were well under 2hrs.
What I'm saying is, that even tho it may be "technically" a slower lead, it's still capable of quick charging. As even tho it was a couple mins slower than a USBC/c 3.0 lead.
Do ya get me... If not I'm sure @elmo41683 or @nigelhealy can explain it better.