Well that sort of makes sense. If Nikola is worth $35B and they have little IP and no manufacturing, then the Tesla Semi program is certainly worth more than that. And maybe the portion that was "priced-in" for the Semi was $16B under valued.
Perhaps it was, but I don't think moving up the production timeline with so few details as "it’s time to go all out" justifies an incremental $16B in one day.
As for Nikola, you are very generous using the word "worth".