He'll likely be right on all 3 but only because 1 company in each will disproportionately skew. His bet is overly broad.

Palantir and SpaceX are very promising companies, it's hard to say if their true value will be realized by 2020.

Stripe alone is worth $10-15B if you ask me.

Where he might stumble is the 3rd, however finding $3B of worth in what must be 30+ companies shouldn't be hard, depends how badly the global economy slows in the next 4 years.

I'm not sure this really does much to disprove the insular and bubbly nature of technology investment, however.