All this weeping and wailing over the switch from aluminum to plastic is kinda amusing. I'm not the oldest old fart on this forum, but I can remember the cries of outrage, gnashing of teeth and rending of clothing when American manufacturers started putting aluminum trigger guards and floorplates on their bolt guns. The Garcia Bronco and Armalite AR-7 were "cheap" .22's because they were made of "alloy".
Now, as others have pointed out, the in-demand "black rifles" are all made of aluminum and plastic. With the phenomenally successful Glock pistol leading the way, the aluminum-framed models that started easing out all-steel pistols are themselves being supplanted by polymer-framed designs.
The (arsenal rebuilt) Garands and 1911's of WWII are being used by a third generation, and earlier earlier Mausers, Springfields, SAA Colts, Remington Rolling Blocks, etc. are being used by 4th, 5th, even 6th generations. Will our "plastic" guns hold up as well? Only time will tell.