I would surmise that the WT are fully aware of the slow death and are prepared for it.
I can see at JW world where the growth of years past are replaced by decreases, not just odd ones here and there but marked globally noticable and not denied by the GB. In fact, used by the GB to keep themselves relevant.
As numbers reverse and congregations are merged instead of split off and made to share halls, they will also have the obvious elder bleed. It would not be inconceivable for them to drop the current elder, MS arrangement with a bit of new light and go back to the old days of one person as congregation servant. One man in charge of each congregation, laying the law down exactly as issued down the line. Maybe even allowing sisiters to do a few things as they do in areas of very low male publishers.
They are getting tighter and more culty than ever with the whole obey attitude. Losses are easy to pass off to the rank and file as being cleansed from the organization. Easy to tell the rank and file that the end is so close that there is no need for more congregations, it's time to bunker down and obey even more than ever, the preaching work is all but finished to 'jehovahs' satisfaction.
I see smaller groups, tightly controlled by less men weilding greater power. The low pool of good men willing to be used will leave the bottom dwellers to rise as 'elders' to abuse the flock. Something that will no doubt suit the corrupt men at the top while they screw as much money as they can from the sheep to keep themselves in comfort.
I see them becoming less relevant (is that possible?) than ever and becoming a quaint little fly under the radar high control group with meetings in gated conventions. One that people will by and large forget about as some annoying door knockers of days gone by.
Not a pretty situation for those that remain in.