I don't think they have sold out their principles. These are their principles.

Thiel thinks democracy and freedom are incompatible. Thiel thinks women getting the vote was bad. Thiel's ambition is to "escape" democracy by seasteading or by building "freedom cities" or "network states":

https://www.cato-unbound.org/2009/04/13/peter-thiel/educatio...

https://www.politico.com/magazine/story/2016/11/donald-trump...

https://www.thenerdreich.com/trumps-weird-freedom-cities-and...

It's a juvenile perspective. It's John Galt cosplay.

They think they will build a utopia. In reality what they're proposing is garden variety authoritarianism.