Back to peronismo after a 1 term Milei presidency?
Time is a flat circle, perhaps here more than other places lol
As to whether he'll fix anything, I doubt it, and will be the first to admit that I don't want him to be President, even though I would benefit from many of his policy positions. Talking with people who are interested in voting for him the consensus seems to be that they think things can't be made worse (perhaps I'm a pessimist but I still think they can, I thought things were bad under Cristina).
Regarding governing, you're right, he won't have Congress, but he can ignore them more or less in the same ways that Alberto has, which would be ironic. For years the Ks have been using DNUs to invent new taxes, change withholding rates for the campo, prevent the import of goods, manipulate the dollar, etc. and the opposition has been crying foul saying this is usurping their domain, while Alberto/Cristina/Massa just laugh, and if Milei wins, you better believe he's going to use DNUs to accomplish as much of his agenda that Congress refuses to take up or pass.
Even if it's Laretta or Bullrich you're going to likely see DNUs aimed at lowering withholding, eliminating the impuesto PAIS, setting perceptions to 0%, etc. and thanks to inflation of 100%+ a year you can cut social plans by simply not adjusting their value for inflation; if a plan pays 30K/month this year it will only be worth $19,135 ARS in todays' pesos in a year.