Its common between “legal workers”. I, for instance usually get a rise per year, but if inflation rate surpases certain level, the rise is either renegotiated or just adjusted by inflation. It helps but it always falls behind inflation. 2 years ago i was earning like 200k AR$ monthly (roughly 600 US$ in black market currency), now im doing 850k AR$ (roughly 850 US$ BM, it was 600US$ pre milei) + 115k AR$ with a second job.
Im not unionized.
A big chunk of Argentina’s workers are non legal ones (usually the worker gets either a bigger pay or gets to keep universal income for non-employment and the employer avoids some taxes). I dont know what they do on those cases.
Edit: inb4, unions are great. People should be unionized. Im against unions in Argentina though, most of them have become a mafia in every sense of the word.