Surferbum- Your assumption that cross fitters are healthier then powerlifters is bullshit. Yea, there are a lot of lazy fat powerlifter but some do pay attention to conditioning and are very healthy.
Another thing the makes you sound like an idiot is saying you stopped lifting "heavy". There is not such thing as fucking heavy. If your body has fully adapted to the weight and you are using proper form then there is no difference in squatting 135 or 315 safety wise.
Now my person opinion is that a lot of people quit lifting "heavy" cause its fucking hard. It a bitch to learn proper technique on some of the more complicated lifts. Doing squats and deadlifts are hard, and a lot of people just don't have the mind for it. Crossfit is just an easier thing for them. Building a cardiovascular base is much easier then building strength imo.