He has not had many successes. He's had a very few out of a great many. Like literally anyone with his connections and money could expect to have. The Facebook deal was dropped in his lap by Reid Hoffman due to a conflict of interest he had.

Probably the most damning evidence of his lack of genius is when he pushed Zuckerberg very hard to sell Facebook at like $1 billion.

He also sold PayPal early in a similar situation and has pushed other founders to sell early, though I forget the specific examples.

This is very clearly not genius levels of vision. Thiel wouldn't be a famous billionaire today if Zuckerberg had listened to his advice.

There's also the fact that Elon Musk showed us exactly what a real genius could do with his incredibly privileged position in the world.