If you read the literature, they compare a symptomatic viral infection to having your hand or foot broken, or a pelvic fracture, or a mild to severe head trauma. I do not see any evidence of those things being equivalent.
When measuring economic impact, they could very well be equivalent. A dollar lost when someone can't work due to a broken bone is economically equivalent to a dollar lost when someone bedridden with a virus.
Best case, your comment is an oversimplification of what the authors spent a dozen or so pages explaining. The limitations they describe perhaps encompass some of your concern. They also describe alternative calculations.