Writer's Fallout Shelter

To totally miss the main point of your post, the idea of typing and talking at the same time is a deeper and more interesting one than most people think about. It has to do with the way people's brains work, how they developed their thinking. There's some people who can talk and type at the same time, but those people may not be able to type and count at the same time, or count and talk, or type and listen to someone else, etc. It isn't necessarily the pure thinking ability of people, but the way they think that allows for certain multitasks and not others.