I started a separate thread about this, not realizing this one existed - my bad. I purchased my brand new X in Sept 2019 and it "shuddered" right out of the lot. Multiple chats with the local service person (who basically blew me off) and finally visited the Portland service center - who said this was a "feature" of the new drivetrain and to not worry about it unless it got worse. We don't drive it much (about 6k miles on it now), and so it hasn't gotten any worse - but is definitely still present. I can get changes in behavior by lowering the suspension, though that doesn't sound like a good long-term solution.
I have been holding off on ordering a new Tesla because of this issue and I really do not want to battle them over it.
I guess my experience would say they probably haven't fixed it yet