By that same argument, any race could be any class, they just have to write a reason for it…
But they haven’t done that, they still think lore reasons are valid enough. I agree, for now.
Also, to be clear, they have said opening Dracthyr to other classes in the future is a possibility, not a definite.
I think the most amusing solution would be to let them be DH in 11 so the race can have all 4 roles, but only two at a time.