It failed because the intent was to cut costs and they got what they paid for. The successful ones were genuinely trying to expand their engineering talent pool and quickly figured out that the cost savings were a marginal benefit that made up for some of the extra overhead of international accounting and management. Quality engineers are one visa lottery away from Western salaries so the local median salary is often completely disconnected from what a FAANG might pay for a decent engineer, which is a rude awakening for anyone trying to cut costs without destroying the quality of their output. On top of that, the people most likely to make it a smooth transition are also the people most in demand (arms race!) and competition for them helps evaporate any savings for the business.

The guy in Argentina is in a great position to get hired to work remotely for an American company, but I don't seem him as competition regardless of how good he is. It's an arms race so my employer's competitor can't replace their team with Argentinians because that down time will give my employer time to crush them (which we learned in the 2000s). They can hire an extra team of Argentinians on top of their existing head count but if they do that my employer will be pressured to hire a team of Brazilians. Before you know it, both companies are hiring even more local teams to help manage the flow of work between their existing local teams and the outsourced ones.

There's more work and money to pay for it than there are people to do it. Until that changes, we're not the ones competing, the employers are.