I've lived in BA for almost 5 years, but have spent limited time in Cordoba, Mendoza, and other parts of Argentina, so I can only really give my opinion on BA. Never been to Thailand.
First, BA IS expensive. While it's a bargain compared to other large cities like NY or London, Argentina is still getting hit by 20-25% annual inflation. If you have dollars, you can trade them at black market exchange houses at get a 6 peso to 1 dollar rate instead of the normal 4.5 peso to 1 dollar rate, but you have to be willing to take the risk of trying to communicate with these people in Spanish, as I doubt they speak much English.
However, your rental contract (if you rent your own apartment) will be in dollars, so you will not save anything there. A temporary studio apartment with everything included will be about $800/month with everything included, so not particularly cheap. You can rent a room in a nice area of town for $400-$500/month. 2k/month is more than enough to get by in BA assuming. You just have to be more careful than probably in Thailand.
The Porteñas (girls born and raised in BA) ARE stuck-up and think their shit doesn't stink, but want to fuck just like any other human being. You win major points being a foreigner since most Argentine dudes don't have a fucking clue and the local women hate them, but it is normally just that: points -- not a guarantee. It's ridiculously easy to make-out with a chick at a party, club or bar (which like someone said above get going around 1am and don't close until about 7am), but fuck on the first night is somewhat uncommon. If you do get their number and manage to get a date (a TON flake. Argentine people IN GENERAL flake all the time), they'll almost always fuck on the first date. They're not going to be as submissive and foreigner lovestruck as the Thai women, but they are fun to flirt and talk to. Most young people in BA speak passable English. Not so much in Cordoba or other cities in Argentina. To me, however, learning the language is part of the fun, and it's FUN to struggle and flirt with cute little 18 year old Argentine girls in broken Spanish. They absolutely love it, and I kind of wish I could sometimes go back to the days where I didn't fluently speak Spanish
The women are hot and in good shape.
The people in BA are, for a big city, quite nice, although they do have the big city asshole-ness/Argentine arrogance. You might enjoy Cordoba or Mendoza as Argentine people outside of the Buenos Aires capital are some of the most warm, friendly, and gracious people I've ever met. The majority of my friends here in BA are Argentines from outside of Buenos Aires who came to the city to study/work.
The steak is good, Quilmes does suck, and the food is kind of bland, but I love it here.