Sorry for my sarcastic smart-assed post! I had a bad day yesterday!
I’m a nice guy otherwise.
IMHO, as with the 737NG, a brand new supercritical wing design would further improve the performance of the 747, allowing it to fly either higher or farther or with even lower operating costs than the proposed 747XQLR.
One example: as with the “old”737, the 747 is fitted with very complex & heavy triple slotted flaps. In contrast, the supercritical wing of the 737 NG enabled Boeing to fit the aircraft with simpler & lighter double slotted flaps while substantially improving the aerodynamic efficiency of the wing. As a result, the 737NG is to some extend outperforming the A320 whereas the “old” 737 was far behind.
Additionally, DFBW could enable Boeing to somewhat reduce the inherent stability of the aircraft & consequently reduce the aerodynamic drag. DFBW could also allow a complete cross qualification with the 777, reducing training costs.
True, a brand new wing & DFBW would be costly to develop & obviously Boeing has carefully weighted the costs & benefits and decided against it this time
What prompted my comment was that the incremental steps approach taken by Boeing with the 744X QLR might not IMHO be good enough to compete with the A346/A380 in the long run.
But again, I don't work for Boeing, I don't know what their strategy is ;this is pure speculation & I’m not really qualified to comment on those issues anyway.