This is one of those things with a standard answer... perhaps they can, but they have have their reasons for not doing it. Perhaps because it would require retooling and a high capital cost, and a lot more field testing, perhaps they tried a 6lb trigger and found it unreliable. Or maybe Germans just have stronger trigger fingers than Americans and wonder what the big deal is with 8lb triggers.
In the end, the best thing to do is become proficient with whatever gun you have, as it is. If you cant shoot it comfortably and accurately, find something that you like better.