A presidential veto is a big deal, especially going against his own party whose support will be critical for getting anything done (or staving off those pesky ethics investigations).
I don't think Thiel has that kind of juice. Maybe Bannon does but it really seems like this would have to be an issue he cares deeply about personally, and it's hard to think of one where there's much space between the president and the modern GOP.
I should have added last night that those are the pragmatic reasons why I don't think that's likely. The stronger argument is that Thiel's most likely reaction is going to be expanding Palantir's data sources or investing in more data mining companies.
