My first thought was that this was very un-Libertarian of Milei, and then I got my answer:
José Luis Espert, a legislator in Bullrich’s Together for Change alliance, which is in coalition with Milei’s Liberty Advances party, replied with a three-word phrase: “Prison or bullet.”
Milei did not even say these lines.
It seems to be mostly about cracking down on disruptive protests that block traffic, etc.
Some of this just isn't that bad:
It also limits the participation of teenagers in social protests, ruling that parents of youngsters who should have been at school instead of protesting will be sanctioned.