My experience here with lines has been OK, not terrible not great. I've had a few people blatantly cut the line, an obvious street drunk almost attacked me when I told him to get to the back of the line. But in general people have been OK about lines. Certainly some oblivious people, but once you do a quick glare they realize their mistake and apologize and move to the back.
I do definitely notice the lack of respect for personal space, even in areas with plenty of space to make a line.
Probably the thing that frustrates me the most is boarding a plane. As soon as boarding starts for special groups (e.g. handicapped, elderly etc) every Argentine rushes the gate even when it's not their boarding group for awhile. They're not exactly cutting because they don't try and board before their turn, but they make it impossible to get to the gate. When I'm in boarding group 1 it's a major effort to get to the gate. It's most noticeable when boarding a flight from the US to Argentina. The gate attendants will plead multiple times with people to step away from the boarding area until your group has been called. They say this in Spanish and English but Argentines just ignore it completely.