I don't know for sure, but I think if you were to load all the configs up for all games, the memory would have to be large/r. This could increase the size of the unit itself, and possibly increase the cost as well.
I guess I'm used to taking the time to make sure my bindings are what I feel is comfortable. Especially when I reformat my hdd, or reinstall a game, or built a new pc.
also, I'm not criticizing or trying to start anything. I find it odd for a request for something that all you have to do is spend maybe 5-10 mins setting the sensitivity and buttons (which most button assignment is adequate).
I wish consoles games would let you bind every action to whichever key is comfy to the player. FO4 came close, but then added 2 actions to some of the buttons which is dumb.