His proposal is directly based on the book "Dolarización: Una Solución para la Argentina" (Dolarization: A solution for Argentina) [1] by Nicolas Cachanosky and Emilio Ocampo, two great economists. You may not be on board with Ocampo and Cachanosky's idea but saying that Milei is only advocating for this because he's a "jackass" is pretty stupid. There is theory behind this.
[1]: https://dolarizacionunasolucionparaargentina.com/