This won't have much effect on the typical Argy.
According to the National Rural Land Registry, foreigners own roughly 5% to 6% of Argentina's total rural land (about 16 million hectares). Of that specific 6% slice, nearly 80% is concentrated in the hands of just 253 individuals and multinational companies.
While it is not restricted to just 1,000 people, overall land ownership in Argentina is still drastically unequal. According to the UN's Food and Agriculture Organization (FAO) and national census data, "non-family farms" (corporate or large-scale agribusinesses) make up about 23% of all farms but control roughly 79% of Argentina's agricultural land. Conversely, everyday family farms make up 75% of the agricultural operations but only hold about 18% of the land.
Historically, the relaxation of the 2011 Rural Land Law (which originally capped foreign ownership at 15% nationally and 1,000 hectares in prime zones) does not trigger a mass influx of middle-class foreign buyers. Instead, it paves the way for massive multinational corporations -such as mining conglomerates looking for lithium, or global agribusinesses to acquire huge tracts of land for resource extraction, effectively validating your point about exporting raw materials and keeping the wealth abroad.
That is what this new law is all about. The rich will get richer and foreign companies can come in and export the raw materials at low prices and keep the money outside of Argentina.