The only confirmed change in Argentina to be aware of is that it will become mandatory in January to have a PCR test within 72 hours prior to boarding any flight to Argentina - residents included. At the moment it is optional for residents.
When you say 'residents', do you mean perm residents sans citizenship, or citizens included? The latter would constitute bloody dictatorship...
I'd expect IATA to push for that. As of now PCR cost in Canada is anywhere between 250 and 500 bucks, with some provinces not even providing it but for essential travel, and the results take up to 6 days. I can't imagine this still being required a year down the road - a lot of people will just opt to go to a country which accepts a vaccination passport, which is a free bee - rather than going through the hassle of getting a PCR and shelling another few hundred bucks for it...Not that Argentina will care to miss yet another opportunity to make an extra penny on tourism...