I think the reason AIBs aren't jumping at the opportunity is probably because this reference design would show up half the AIBs top end designs, to make a cooler than get push 300W out of such a small surface area is no easy feat, infact it's something no ones ever had to attempt before on this scale, while capable vapour chamber designs wouldn't need much alteration any heatpipe based design would likely need some careful reconfiguring to make sure things are optimal, and only the beefier AIB coolers would be relevant, which rules out a few companies.