His head-over-heels support for a decidedly anti-libertarian candidate like Trump is in itself quite extremist. This has always been one of the standard tools for (crypto-)fascists and closet authoritarians of all ilks to get into positions of influence -- by using people of nominally "opposing" viewpoints as, in effect, wedge instruments to disrupt the system as violently as possible -- and then step into the emergent vacuum.
And somewhat secondarily, there are the antics of his pals at the Seasteading Institute in blatantly courting partnership with the government in Honduras (basically the most murderous government left in the hemisphere) in order to set up a libertarian microstate in the heart of certain piece of "jungle" that just so happens to also be claimed by one of the region's poorest and most ill-treated ethnic groups.
Thiel's own role in this venture (if any) is unclear -- but his association with the SSI (and the principle actors in this "venture") is well-established.
Is Trump anti-libertarian? His policies seem fairly libertarian to me. I suppose being anti-abortion could be considered anti-libertarian, and maybe you could frame his immigration stance as non-libertarian? But i'm not sure. Libertarians don't necessarily extend their liberty to non-citizens.
Are you thinking of some others? I'm perfectly willing to be wrong about this. I just can't think of any major instances where he deviates from what i'd consider to be a libertarian agenda.
2) He didn't get half the country to vote for him. It looks like around 55-60% of voters turned out this year (the whole tally isn't calculated yet). Of those, he got less than 50% (as Clinton got more votes than him). So at best he seems to have gotten around 30% of the voters to vote for him. Not everyone is a voter (age, other disqualifying factors). So even if he had somehow gotten 50% of voters (which, again, he didn't), he'd still have less than half the country voting for him.
He argues that "climate science" is not real science because it has "science" in the name. I'm serious.