I just learned that Brown-Forman has cut the proof of Woodford Reserve, also just for non-U.S. markets. No change for the USA. The new product is in the pipeline now.
I just talked to Chris Morris about it and he says it was driven primarily by consumer preferences and the fact that, especially where bourbon is not well developed, most other spirits products are 80 proof and even lower.
I suspect Beam and BF are doing it for the same reasons, which would be a combination of the reasons both have stated. The international consumers, especially the mainstream ones (not the crazies like us) tend to prefer a lower proof. Chris said the international standard for premium expressions is 86.4 proof, but even a lot of the prestige single malts are 80.
But, obviously, everybody in the whiskey biz is trying to make the whiskey they have go as far as possible and watering it certain helps.
Chris says that since Woodford bottles by bottle size, when the 70 cl bottles are up, they mix a batch of the lower proof, and make a lot of adjustments to filtering and stuff to keep the taste as close as possible. It's not just a batch of the U.S. expression with a little more water.