Javier Milei certainly looks and sounds like a right-wing populist. He has the swagger, the anger, and the reactionary views on social issues to fit the bill. But Milei is operating in an environment in which populist economics are the status quo. As a result, he ran as a radical deregulator. Think of Paul Ryan’s head on Trump’s body.
This unusual combination of CL and Reactionary, reminiscent of the Tea Party, probably won’t work in the end, because CL economic measures are the very antithesis of populism. They promise long-term gain in exchange for intense short-term pain that is typically intolerable for a reasonably prosperous democratic electorate. They can only work if the country as a whole is so fed up with the existing system, it feels it has nothing to lose (Poland and the Baltic states) or if the government is willing and able to use force to impose them (Pinochet). Milei is not in a position to do the latter, and it is doubtful that Argentina as a whole is ready for the former.
The real irony here, of course, is that Trump is a Peronist at heart. The success of his Argentinian right-wing counterpart and the economic failures of the previous government should operate as a warning to him. Not that they will.