Originally Posted by
honu
For the longest time, AAdvantage has allowed only the most expensive CX economy fares to qualify for mileage accrual. It's no surprise that the only the same expensive KA fares now qualify too. But not all OW airlines put this restriction on CX- or KA-flown miles. With CX's own program Asia Miles, and with QF's FF program, there are fewer earning restrictions, so you can earn points/miles also with K, L, M, and V fares. If you already are a member of either program, you could try to get credit for those KA flights.
I don't think it is a matter of what Aadvantage allows, but what the airlines choose to pay for. CX feels that it should only buy AA miles for passengers on higher fares. Logically it makes sense to pay miles to people that aren't choosing you because you are the cheapest.