The words "user" and "experience" have been used in the same sentence for a while. Both the topic and the role have been evolving for a while.
Here's Here's a paper that I delivered at an early "before we called it the Web" conference on interactive systems in 1984 titled "Interactive Architecture and the role of the Designer" http://www.jcvtcs.com/papers-tcs/interactive-architecture.html
I ocr'ed that old paper and converted it into an html page, with a "punchline" that I replaced old out-of-date terms with their more modern equivalents: http://www.jcvtcs.com/services/architecture-metaphors.html.