To clarify a few things, since I can:
“Free” FP will still be available as they are now. However they may not be free for the more popular attractions, or the ratio of “free” fast passes for the more popular attractions may be reduced. The ratio may be fluid, or alter over time. You may find you can’t get a “free” fastpass for Mine Train since they’ve “all run out” but you may then magically be able to pay for one.
There may be at least three different packages of paid fast pass available. As I understand it there maybe a limit on re rides (no more fast passing BTM then getting another one in the same day)
This may be implemented on the newest and shiniest attractions first, once said attractions begin to take fastpass. The ratio here will possibly start quite low in favour of free passes and slowly be altered.
This may happen later this year.
That evolution vs. revolution approach would make sense. And provide justification and a dedicated revenue stream for new attractions.
This could get pretty scary if you think of it as 'in-app purchases' when you are waiting in a 180min line and a FP+ Platinum pass is available for that ride for $20 or $30, that suddenly feels 'worth it' for a smaller party and rack up a lot of charges to your account without really thinking about it.