Very true. Heck, this thread started out with a discussion of how much better a .243 Winchester or .260 would be as a standard round.
Thing is, then you've got to convince ALL the NATO and other allied countries to switch, which means switching ALL those rifles, SAWs, and belts and magazines as well. It would seem that they're not quite ready to go that far, or expend that much money just yet, especially since some nations simply could not afford to do so at all.
From the articles, it seems clear that, for now, the approach that they're taking is to see how much the effectiveness of the .223 round can be increased via different weights and loads, and of course, adding a grenade launcher.
Just for the standardization issue alone, I wouldn't expect a total cartridge switch for at least another generation. Sad, really, as standardization was intended to SOLVE problems, not cause them.
Fact is, American civilian shooters always led the way on new rounds for the military. We always had the best, up until we had to clear it all through the Euros.