I never said that it couldn't be used by someone who isn't a power user. In reality I think anyone can be a power user on Linux as it is fairly accessible and easy to learn. You don't need to be some crazy wizard to use the command line.
People will disagree and downvote but objectively you are correct. Who makes the software for linux? Who maintains distributions? Who contributes to OSS? Who donates to OSS software? Who maintains distro wikis? And when these people do it they make it with whom in mind? The answer is simple, its power users who make it primarily with power users in mind. Thats why Linux has more maintainers, more contributors, and more software engineers, than professional software/UX designers (call it a bad thing but thats what it is)