That might be true, but I'm only 134 and have pretty bad ankles and knees, so 60# is probably my top carry weight. For my needs, dropping an extra half pound/three quarters of a pound from pack weight is better than unlimited load capacity I'll never use.
The Ultra 6000 is supposed to be good to what, up to 150#, though some folks doubt their durability. The Paradox packs, which look way better, should carry as much.
To be clear, I'm not trying to beat up on Kifaru by any means. They make good products and have good customer service. Lots of dudes have crazy brand loyalty to the rhino, which means they are doing things right. I think it's a niche issue. Kifaru's niche seems to be bullet-proof, carry anything. I'm personally looking for an ultralight back I can carry the occasional heavy load in. Other companies probably fill my needs a little better, but I am interested in Kifaru to some extent because of that brand loyalty they engender.