Really not seeing the issue here, the hub you have is 4 generations old, and it's 10+ years since they were introduced, which other large bike manufactures still provide individual spares after this time? Shimano are one of the best to support their older components, but they won't support forever, 2 generations is normally the limit; and 7700 is way over this. it's not as if they don't produce hubs which are not 9 speed compatible still, as their whole range less 9700 will work with 9 speed.