IMO, a worst case scenario would be if someone made the disastrous decision to develop an in-house solution from scratch, which is a pretty tough challenge given the complexity. If that’s the case we’ll proably have to wait pretty long for a first alpha release and even longer for a stable one. I can think of several reasons why it might go south.
https://github.com/dyninc/OpenBFDD
https://github.com/FRRouting/frr