As an ambulance chaser I am confident most disability claims should be denied. These cases have exploded over the last decade as job opportunities for obese middle aged workers have been obliterated, dependence on opioids has surged, and the shame of not supporting yourself has largely gone away.
My wife is a physician and the stories you hear are unbelievably sad but most people don't fit the definition of disability by social security. Most people are able to perform another job, however, their training and personality limits them in being reintroduced to the labor markets.
The problem isn't a simple one but there are other solutions such as retraining