I guess I am supposed to have thoughts on Javier Milei.

So here are some. A word of warning, however: I am NOT an Argentina expert, and my Spanish is very weak, at best.

Thus, these thoughts aren't likely to be worth much.

On that note, my take is that the positive outweighs the negative.

Start with the good:

1. Milei advocates big cuts in government spending. A great thing, especially given Argentina's severe fiscal crisis and heavily bloated public sector. This is a way in which he's very different from Trump, who has made a point of opposing cuts to the biggest US spending programs.
2. He advocates unilateral free trade. Another great thing - and even more totally at odds with claims that he's a MAGA nationalist like Trump.
3. He supports legalized organ markets!!!! This is one of my very favorite policy ideas. It can save many thousands of lives each year, Plus, it's an issue of bodily autonomy.
4. The Peronists he defeated are awful. They're responsible for Argentina's high inflation, economic stagnation, and crony capitalism. When it pursued generally free market policies from 1880 to around 1930, Argentina was one of the wealthiest nations in the world, and a magnet for immigrants. The rise of Peronism led to its decline. I won't run a complete comparison. But the Peronists have far more in common with MAGA than Milei does (e.g. - on protectionism and government spending).
5. On foreign policy, Milei is pro-Ukraine, pro-Israel, and hostile to China and Russia. Exactly the right combination! The Ukraine/Russia part is also a contrast with Trump.
6. He wants to replace the Argentine currency with the US dollar. This is less radical than it sounds. Several Latin American nations (Ecuador, El Salvador, Panama) have already done it. It's a good way to credibly commit to fighting inflation for countries that have a history of inflating the currency to pay off their debt. Dollarization isn't perfect (e.g. - it leaves Argentina vulnerable to inflation generated in the US). But it's far preferable to the completely dysfunctional Argentinian peso and central bank.
7. Privatization. Argentina has lots of awful state-owned industries. Milei wants to privatize them. He's right to do so!
8. He's pro same-sex marriage and (most) trans rights. This is another way he's different from the MAGA types.
9. Milei is a true devotee of libertarian economics and political thought. He knows his Hayek, Friedman, and Mises. He even has a dog named after Robert Lucas (unimportant in itself, but an indication of the depth of his knowledge and interests, as Lucas is only known to serious students of economics). This increases the likelihood he's serious about pursuing these ideas.

The bad:

1. He's pro-life and wants to hold a referendum to curtail abortion rights. This is a genuinely hard issue that divides libertarians. But I'm with the pro-choice majority. On the plus side, abortion is popular in Argentina, and Milei will likely lose the referendum if he does hold it.
2. He praises Trump and Bolsonaro and they praise him. This may be just mood affiliation. The Latin American left hates all three of them, and Milei hates the left. But could also indicate genuine authoritarian tendencies.
3. He wants to institute some modest, but still bad immigration restrictions. This would still leave Argentina much more open than the US even under Democratic administrations. But still a step in the wrong direction.
4. He has little political experience and his nascent party has very few seats in either house of the Argentinian Congress, and does not control any of the country's state governments (Argentina's system of federalism and separation of powers is roughly modeled on that of the US). This will make it hard for him to implement his reforms, and increases the risk of failure.
5. He claims to have communicated with his dead dog, and even to have gotten advice from the dog. Unimportant in itself. But could be evidence of bad judgment and/or instability.
6. It's a mistake to think that his win is a model for libertarian success elsewhere. In most respects, it's a product of Argentina's specific (and awful) economic history and current political situation. Importantly, it's much easier for third parties to break through in their system than in ours.

If Milei manages to implement any substantial part of his ideas, it would be a great thing. But he could also end up falling flat on his face. Time will tell. Overall, however, my tentative view is that his win is a good thing, especially considering the awful alternative.