Can you expand on your comment - what "current setup" are you referring to? What is the basis for your conclusion?

Presumably, you cannot currently earn miles in any oneworld program for MH flights. Although the mileage earning between airlines and programs is a result of reciprocal agreements, ultimately (come February 1) it's up to MH to decide how many miles you'll earn in another oneworld airline's program (be that AsiaMiles, Aadvantage, QF etc) for a flight on MH. Hopefully, MH will be keen to get oneworld fliers to use its flights and will give 100% (or more) miles on all fare classes, including discount economy classes. Given that there are presumably no current mileage agreements between MH and any oneworld airline, I for one have no basis on which to speculate as to what MH will do.

Some airlines are keener than others to get business. As an AA flier, CX will only give me (AA) miles for (economy) flights in Y, B or H. However, AY for example will give me AA miles for (more or less) any fare class. As a result, I'll happily buy a discounted economy ticket from AY but I'm never going to buy one from CX (and am generally not going to trade up to Y, B or H on CX unless I absolutely have no choice but to fly CX). MH may or may not want my discount economy business - if they do, they'll follow the AY approach, if not, they'll follow the CX approach. The decision by a number of oneworld airlines (notably CX, QF) not to give AA miles for L fares means their flights are not usable for economy RTW tickets (unless earning no miles is acceptable to you) - let's hope MH does not follow their example.