I've been using the older, white version of this cable for over a year now, charges at full speed and is 10 feet long. https://www.amazon.com/dp/B07LF1FNRV/ref=cm_sw_r_other_apa_i_NipPDbG9S27VG
My requirements were similar. You may want to check out AllThingsOnePlace on YouTube, they publish straightforward but well-researched reviews of PD chargers.
I went with a Baseus 100W GaN charger after positive reviews. Works well for both my Intel ThinkPad (65W) and AMD Ryzen Yoga (100W).
Before the Yoga I used an Aukey PA-B4 (65W). Truly amazingly small and lightweight.
The cable I use is this 10ft 100W UNI PD cable - having ten foot (4.5m) of cable reach available is perfect and I have yet to find others like it.
The culprit ended up being the included braded cable that came with the Chroma Core X inside of the box (now i am not sure if its original or not, because i ordered Chroma Core X from Amazon Warehouse, the cable inside has "uni" logo) but it seemed like the insides were untouched.
Yeah. The Razer Core X supplied cable is neither braided nor branded "Uni".
But Amazon does sell such a cable: https://www.amazon.com/uni-Braided-Compatible-MacBook-Galaxy/dp/B07LF1FNRV
Sort it out razer!
Sounds like an Amazon Warehouse issue rather than Razer.