Exports have been rising because Abe's economic plan was to decrease the value of the yen. Japanese index funds have had crazy returns in the last 3 years because of this. It was also suppose to get people to buy more domestic made products. The real issue is still the shrinking population and the moving of production to cheaper countries like China and Vietnam.Yea not to mention that their Asian neighbors are closing the gap when it comes to vehicles and electronics, plus Japan has territory disputes in the region (and not just with China) which doesn't help. But I think their exports have actually been rising anyway.
Time will tell how Abenomics, especially with weaker support, will hold up.
Also how advance a nation is has nothing to do with the health of its economy. You could argue the opposite easily. Highly advanced robotic production has little use for workers.