I spend too much time looking at Reddit, and I've seen the same thing. I wasn't too surprised when Milei won, though I thought there was a slight edge for Massa.This is by no means a rigourous analysis, but the comments in my IG news feeds (Clarin, La Nacion, Infobae) have gone to being almost uniformly negative now. Before you'd see "te banco mi presidente", or "te votaria de nuevo", now the chatterati regret their vote, and are damning in their condemnation of Ms. 3% ("alta coimera"), of the toadying to Trump (with the conditions attached to a bailout), and the fawning over Israel.
Among my IRL Argie acquaintances, there was a mix, but tending anti-Milei. I meet a lot of musicians (anti-Milei) and people who want to practice their English (pro-Milei). Taxi and Uber drivers, as well as tango dancers, seemed evenly split.
But on Reddit there was a LOT of energy for LLA, whether real or artificial, which felt very much like when Trump won the first time.
For the second Trump election, online felt like it does now for Milei: less vocal supporters, more criticism and 'anti' sentiment (people who like Milei's ideas, but don't like him any more), and a small group of ride-or-die fans. But Trump pulled it off, so there may be a vast reservoir of 'offline' support we don't see for LLA either IRL or online.