Many of these frameworks won't disappear but I think adapt to the newer trends.
Whether we like it or not java is still here and used, I don't see why rails and django won't be.
The whole point of software is it evolves. These projects both have enough of a following to receive updates to fit those new paradigms.
They may not be as suited for something built from the ground up for that specific use case, but that doesn't mean they will disappear.