intentionally popping the back and other joints?

Is this good for anybody? Is it healthy?

Generally it doesn't matter.
However, too much of it causes instability in the joints.
If your joint was supposed to go that far then it would. If you developed stiffness over the years then stretch it slowly and it will come along... If you keep pushing the joint through a higher than normal force you run risk of injuring the ligaments and joint... The older you get the more spurs and rough spots on the joint you get thereby increasing the risk of injury....
So essentially, if you don't need to do it... Don't.

Like recommended before, I wouldnt be doing that too often. Instead, perform frequent stretches to get loose. I wouldnt be trying to pop my joints unless it is due to a legit stretch.