No, I mean the alt-right is mostly made up of former libertarians. It's where the Paulites of 2008 and 2012 went.
Far be it from me to offer a word in defense of libertarians - I have always found it quaint and rather touching that there is a movement in the US that thinks Americans are not yet selfish enough" - but this has less to do with sincere and self-professed libertarians moving toward fascism than with the grotesque grab-bag that comprised Paul's coalition: Buchananites, survivalists, anti-vaxers, 9/11 truthers, anti-fluoride people, neopagans, and every other variety of marginalized, conspiracy-spinning oddball.
No true Scotsman. The Paulite coalition may have been full of cranks, but that hardly means it wasn't full of sincere libertarians either. Austrian economics is kinda inherently cranky.