Fact: If you are talking osteo and cardio PREVENTION no study has shown squat/deadlift/bench to be superior to any other resistance exercise. So touting this for a "you gotta squat!" is quite sketchy since many of the studies use machine weights rather than free weight exercises.
When you already have these disorders its on a sliding scale from mild to severe and what you can do in a gym will be determined by where on that scale you fall. And if you really think this is only applicable to 0.5% of the population at large you gotta bone up on your health statistics.
The point is that you actually don't need to do these things as prescribed by Rip to get strong and stay healthy. They are tools to be used for sure. But use them for the right jobs.
An active lifesyle/job may very well be all you need if your goals are simply health and longevity... in fact studies several epidemiological studies sure appear to support this.
I deal more frequently with people who have the above maladies so perhaps I'm a bit more cognizant of their reality. Its far different from a weak otherwise able bodied individual just trying to get stronger. I think pushing Rip on 100% of the population is just as bad as telling every single person that ketosis is the only way to live and if they can't do it they will never be healthy.