But if you are merely becoming a pro at using that 1 tool you are likely not thinking past how to use that tool.
To give an idea of how bizarre it has gotten, I'm seeing a ridiculous number of job ads for senior software positions that list "git and GitHub" as either requirements or nice-to-haves. To me that's like asking for the ability to use a pencil and paper in an engineering design position. Anyone remotely qualified will have said experience, or be able to come up to speed on it in a day or three. It's like HR just has to make that list of tools as long as humanly possible.
Take anyone who has used Mercurial or any other modern distributed source control system and sit 'em in front of git and they'll be fine within a very short time. Take anyone who has used Eclipse and sit 'em in front of Visual (or vice versa) and they'll be able to do the job adequately almost immediately. They won't know all the stupid Visual tricks that someone who has used it since 6.0 days knows, but so what?
And if a person is not capable of that, you've made a bad hire, because technology and tools change all the time, and if the can't adapt to your toolset they won't be able to adapt to the future. So there is absolutely no loss to a company in hiring someone unfamiliar with their specific tooling. There might even be a gain, because if they fail to adapt they can be let go painlessly while still on probation.
So long as companies continue to use toolprint matching for hiring, schools will focus on teaching the tool-du-jour.