Its likely better the closer we can get to nature...but what I really think is that there are adaptations we have to make in keeping chameleons in captivity in order for them to survive in a healthy manner.
In nature in their own habitat or in a habitat in another country that is very similar its different than in a cage in a climate where they can not be kept naturally...and we need to do whatever we can in that situation to keep them the best that we can. If doing things like growing them slower, supplementing them the best we can, gutloading the insects, etc. enables them to grow into healthy adults that live long lives and that can produce healthy offspring is what it takes, then we should be doing that.
In nature in their own habitat or in a habitat in another country that is very similar its different than in a cage in a climate where they can not be kept naturally...and we need to do whatever we can in that situation to keep them the best that we can. If doing things like growing them slower, supplementing them the best we can, gutloading the insects, etc. enables them to grow into healthy adults that live long lives and that can produce healthy offspring is what it takes, then we should be doing that.