by Oph. The new Steam Controller page questions from people:

A: I’m a very happy Steam user who is happy to use his cheerful mouse and keyboard. Do I want a controller?
A: You can’t turn a sentence into a question by just adding a question mark at the end. But we’re glad you’re happy, and in any case, please use the method of input that you like the most. Be sure we will not leave you. We also love mouse and keyboard.