It's prob true about a leaner body meaning less stress on the system. All the cultures known for extraordinary longevity consume far few calories than Americans. In fact, it's rare to see an elder Okinawan overweight, for instance.
It's a little shocking to see a former competitive bodybuilder lose mass like that but who cares? Bodybuilding is fun but it should promote health and well-being. Your family, health, and sound state of mind are far more important than how big you look. No one is going to be "Mr.Olympia" forever. Not even Ronnie Coleman.