Well, first look at western porn; it feels cheap, vulgar and I'm pretty sure most of the actresses had taken lots of drugs and underwent through many surgeries. Japanese AV actresses have smooth skin, a delicate body and beautiful faces. They do take more care of themselves, I'm not saying some of them don't do drugs or hadn't gone to the surgeon, but you can tell they'd rather go to the spa or have some healthy hobbies than living on drugs and alcohol.
One of the reasons many westerners prefer japanese porn is precisely that it has scenes with intimacy and eroticism. I've seen that japanese porn actresses kiss and caress a lot in their videos, and that each has their own videos. It's not just having raw, gonzo sex like in the west, but they slowly take their clothes off and even take part in weird, but funny activities in many videos.
Yes, the japanese porn industry might have an overload of girls, and slowly the public is shifting towards a digital medium, BUT, the west does have their own problems; recently amateur porn and camgirls are eating the main porn industry profits, as I say, most of the actresses are really young but you can tell through their pale and depressed faces that they do drugs, and the western public is nowadays hardly finding any sense of intimacy or tenderness at all in western porn.
On the other hand, the Japanese porn industry still has many cute girls and there is still also a physical medium. Blu Rays and DVDs still sell and, unlike the entitled, bitchy western porn actresses, japanese porn actresses act like idols who care about their fans. They hold meetings, sign merchandise, release photo books, appear in doramas and movies, some girls even become singers. And vice versa; many famous gravure and pop idols become AV idols. So Japan is doing far different things than the west, which results in being closer to their fans. Even some western girls are getting tired of doing western porn and going to Japan to make some videos. See Cecil Fujisaki and Amelia Earhart for this.
I personally think the japanese AV industry still has a lot to show. I mean, compare a modern porn western actress to a japanese porn actress. They don't even compare. The western girl looks high, full of silicone and speaks in a very entitled manner. The japanese girl (not all, of course) still has class, elegance, sexiness and cuteness.