On the one hand, I don't think the current JW org will just disappear. But on the other, I agree with nicolaou that the previous form of the organisation is already largely dead since GB 2.0 took over.
I came in just at the tail end of the 'old' organisation (one indication of the change is that it was called "the society" by most in the congregation then, not "the organisation", and that's one way you can still tell the 'old-timers' now - they still say "the society" when speaking about instruction coming from NY).
The big changes that came in after president Henschel died and then the other 'old' GB members like Barber, Barr, Schroeder and Sydlik had all gone - from about 2010 onwards - have transformed the JW organisation beyond recognition from its late 20th century incarnation. This seemed to be lead by the 'new guard' of GB 2.0 who took complete control from the 2010s, with Losch being the longest serving (having only been appointed in 1994). After that, Herd, Lett and Splane arrived in 1999 and Jackson and Morris (who he?) in 2005.
Adopting the blue square corporate logo, introducing the televangelist-style Broadcasting channel, bringing video and cartoons into meetings and conventions, electronic devices everywhere and paper Bibles and books virtually non-existent, releasing completely new songbooks (with awful Disney-fied and cheesy Christian rock style songs) and a changed NWT, scrapping the TMS and reducing the ministry to bite-sized 'Q&A then point to the website or play a video' tactics, introducing public witnessing with carts - the list of changes goes on, most of which are miles away from their practices of the 1990s and earlier, and some of them stand in complete opposition to their beliefs of old (the televangelism of JW Broadcasting and Disney-fication of the Bible for videos, for example).
The quality of the new members also shows a big change too, with far fewer being capable of holding the kind of Bible debates and discussions that JWs baptised and taught prior to the 2000s could, and few being interested in genuinely deep or serious Bible study or discussion.
As has been said, there is virtually no growth from outside these days (which is hardly surprising). Although hours spent on the ministry have been increasing, the quality of teaching is so poor and unconvincing now that it's unlikely to persuade many. It's becoming a case of 'diminishing returns'. I can remember when we used to see annual growth in JWs of more than 3% a year, but that's not been the case for a couple of decades now.
That's likely to slow the pace of the organisation, but it has enough internal structure, unity and momentum to keep it going despite external pressure like opposition and legal actions. As slim said, it takes a long time for a religion to die away, and the JW org has the advantage of being multi-national which protects it somewhat from complete collapse even if it were to wither away in some parts of the world.