I don’t think there will be a tipping point that has the masses leaving in droves. Lots of major changes and disappointments characterise JWs and no major shift downwards in numbers has occurred.
My congregation, where I try to visit as little as I can, has elders in their 40s and 50s with decent jobs and are fairly intelligent so it’s a pretty warm congregation. I guess in this case even where attendees know TTAT they will stay and endure the nonsense because they find a sense of belonging and community.
I do know whenever I socialise with other JWs very rarely do topics revolve around JWs or the good news the JW Kingdom, the discussion is invariably secular, jobs, holidays, sport, people etc.
Where someone is adversely affected because they were or are judged harshly, that might give them cause to question the whole JW world.
Where people work with others e.g. an office environment they are exposed to people who are relatively happy without being a JW, that might give them cause to question. Or, where people like me have reached 50+ hearing the same nonsense for over 50 years i.e. how close we are to the end this will give rise to questioning and then a visit to boards such as this, then you quickly become mentally out of the JW world. (The reason why JWs are told to stay away from website like this).
What I do feel will happen is that a significant number will evolve into nominal JWs like you have nominal Catholics, Protestants etc. who remain for the social aspects.
The young who gain an education, beyond secondary school, will quickly realise that truth is not absolute and to claim JWs have the truth is arrogant and presumptuous at the very least so they’ll leave sooner or later.
The consolidation of assets, sweating the assets i.e. using kingdom halls fully (i.e. most days of the week) and the move to digital rather than print will ensure funding is secure for the future. This means JW.org will not wither and die. It will trundle along with a core of super zealous ones and a merry band of apathetic followers.
My observation of the new ones that get baptised from my congregation, other than children, is they have some type of emotional problem. You don’t get successful people with high income, good jobs, educated and emotionally secure joining.
How many sane people really believe in a few years they’ll be petting lions and tigers, living in a big house on a hill with a stream flowing and an abundance of fruit growing in their large garden with everybody around being their best friend? And, their loved ones will rise from the dead? But wait, this can only be your dream come true if and only if you join and remain loyal to JW.org!