I would argue the other way around. A "professional" gets paid for a job, full stop. A "vocation" derives from "to call", or someone's "calling", as in someone's purpose in life.
Maybe our etymology is what sets us up for work-life imbalance :)
>A "professional" gets paid for a job, full stop
Clergy was the first example where the term derived so I don't know if the roots of the word align with your definition. Granted, colloquial usage changes word meanings over time.
Slight nitpick, but this is the mark of a person with a vocation. A "professional" answers to a higher ethical calling. The name derives from "professing" an oath; for example, for a doctor to "do no harm" or an engineer to work in the public good. This can occur within a 9-5 window, but I would expect that, if needed, a professional would put their oath above clock hours if it was in conflict.