You make a key point: Jobs and work are not the same. Before the industrial age, the words “job” and “employment” had the same connotation we now associate with “chore” or “task.” That is, they referred to an immediate functional activity, not to a vocation or what we might now consider a career.
First, you are missing the point. It’s not ‘total costs of labor for corporations.’ It is income received by employees — as opposed to wages or salary. More and more of the income employees have been receiving has been in the form of benefits. Only because of an accounting anomaly is this income not counted.