You can see the declining FH power of ML, XX and FZD quite clearly with the new ABS ball. Harimoto, Boll and other top Jap players don't seem to be affected much.
From a physics POV it makes sense based on the type of rubber they use.
Passionate about TT
I understand this but I don't fully buy it. The key thing as pointed out by Zhang Jike is that the spin effect of the older balls is gone and you don't win shots off single shots as much and are forced to rally more. This puts the players who have a memory of what a quality shot used to be at a disadvantage as shots that used to win points instinctively are now coming back.
Also some players are getting better at taking the ball earlier per the women's game. Also short pushes are not as secure as they used to be because the spin effect of the short game is not as secure.
But after even saying all this, it comes down to what you built your style to win on not the equipment. Many players switched to Chinese rubber to deal with the plastic ball even the ABS one. A good question is what brand of ball is being used on the Japan Open. I assumed it is the DHS one. But all on all, I think the need to accept that spin is not as effective as it used to be with cellulose and cellulose acetate is what explains some of what you are seeing. But Timo has adjusted magnificently so no one has any excuse. We can see Zhang Jike painfully doing the same. We can also see how players like Lin Gaoyuan and Harimoto are benefitting. So I don't think it is so much equipment as accepting that you have to make certain adjustments to your style.