It is a pity VT is not a system that can evolve though. So is the WT variant more flexable in concept. Possibly more suited to collaboration with other systems?
Who says it can't evolve? Probably has done quite a bit in its development.
We don't have long enough recorded history of it to tell. It is open-ended, though.
But, if two species can't interbreed, does that mean neither of them will evolve?