This is not true. I ordered my 1000w Thor P2 a few weeks ago specifically because all the marketing mentioned it came with a 16 pin cable.
When it came in, it only had a 12 pin cable.
When I called in to Asus support to ask for the 16 pin cable that was promised he acted like he didn't know what I was talking about. I had to eventually pull up asus's own ROG website and read the exact quote that they were advertising on their own website. The 16 pin cable was heavily featured in Asus' own marketing as coming with the 1000w Thor P2.
It also said, on their own website, that if you didn't receive a 16 pin cable with your PSU to reach out to them and they will send you one.
Once I instructed the agent to check their own website and he saw all this he conceeded and took my info down and said someone would reach out to me within a couple days.
Couple days later I get a very brief email from Asus and they just say sorry, the cable is out of stock. No other recourse, no eta on restock.. nothing. Just a sorry, kick rocks... On a $330 PSU lmao.
I emailed back, mentioning that I was rather upset with this as one of the primary reasons I specifically ordered this PSU was because it was supposed to come with a 600w 16 pin 12vhpwr cable.
I asked when they expected to be able to send me my cable and if they are refusing to send something that was marketed as being in the box and wasn't, what other recourse they had in mind.
A few weeks later, I basically got the same brief sorry it's out of stock email with no real elaboration or care.