I had read the OP and was going to comment nearly the exact same thing that EdRooney said (though he surely said it more succinctly than I am usually capable), but I had to go to the supermarket, buy the girls some clothes for a school production tomorrow, etc. Hehe.
Peronism is populism as well. But I think that many people who believe in "Peronism", while mostly wrong-headed (hey, it's my opinion), are probably sincere in their desire to make things better. The fact that it's not a well-defined set of policies makes it easily attack-able by other populists such as Cristina.
The fact is, the K twisted a whole bunch of bizarre thinking together with populism and fascism and this idea that young, inexperienced people can do as well in high-level government jobs as others who have years of experience - just because they have the right beliefs (or so it all seems to me).
That Massa, a peronist, broke completely with Cristina and made his own attempt at the presidency, and then put himself in with Macri (while telling him "we're going to be watching you"), and then Macri actually winning over Cristina's ostensibly peronist candidate, is telling to me how much peronists don't agree that what Cristina was doing was not what they considered to be peronism. The fact that Scioli made it a fairly close run in the end is also telling as to how much it costs many in this society, in these days, to vote other than peronist en masse at least. In fact, I'd bet most of Massa's supporters (well, I don't know, at least half?) voted for Scioli.
The only way I can see peronism being finished here is if Macri gets 8 years in the Pink House, not only turns the economy around, but actually improves things across the board significantly for a whole lot of people of various economic strata, and replaces Peron as the new Culture/Cult Hero. Frankly, I don't see that happening, for a whole slew of reasons which don't have to much to do with Macri himself (yet), as we haven't seen how he will perform to know if he's even capable.
I also see a danger that Cristina could return with her stupidity after 4 years. If Macri completely fails (again, for whatever reason), she's poised to come back and say "see, I told you so. Look at the mess these guys made. Gee whiz guys, I have to come back in and clean things up. Remember how we had no poverty during my time? No unemployment? I'll get us back there again." And Massa, the best peronist (in my opinion) who ran in the campaign, will have been seen by so many voters from the runoff as the guy who sided with the devil against the hero (ostensibly Scioli, from Cristina's point of view). With all the propaganda storm that could be waiting in the wings, Argentinos seem to have variable memories at the "why, who, what and when".
I hope that never happens! I feel that most governments function well-enough for the majority of people when they enforce the laws with everyone and don't try to make special cases for those who "deserve" something special. It's always meddling in things too complex for fine control (at least to date) that causes blow-back that few see coming. Cristina was not only a meddler, but a meddler who had no idea what to do to make things better. And that's giving her the benefit of the doubt that she really to make change for the better, no matter how wrong-headed, and that she wasn't just in it to become another Evita made queen.
Hopefully what Macri's election to the presidency means is an end to Kirchnerism, not Peronism. That would be acceptable to me and probably a whole lot of Argentinos.