Good question, and I had to sit on it for a bit.
Down the list, I'd say more than a couple unique cultural elements exist, and they all had overlapping influence over other cultural elements. The gaucho (gil), the economic and logistical isolation, the "potencia mundial" failure complex, the "viveza" mentality previously discussed in a recent thread, the yerba mate, the fear of spices, the false sole proprietorship of dulce de leche, the (disputed) southernmost point on earth excluding Antarctica (but also including a very significant portion of Antarctica) and other diverse landscapes just hours of perilous off-roading away, the elitist B movies, the stamina of marathon queuing, the self-awarded PhD in economics, discussing the evils of Big Oil and Big Carrefour while padding the mattress with chica grande Franklins from the imperial US that stole their prosperity somehow.....
A peripheral outpost to me means something like Chinatown, or Little Mogadishu, not Argentina nor the portenios (nor the Aussies). Maybe if "New Mediterranea" surfaces somewhere, we have a peripheral outpost.
And the collapse...well...the boom and bust happened really quickly. I think the general and irreparable collapse of Argentina happened at a pace that did not coincide with the decline or collapse of the rest of the west, which, we can agree, is in progress.