I agree that Argentina has much less to spend on roads, and that many roads are pretty funky, having rented cars and driven in Argentina. But in the last ten years, I have seen constant improvement of roads, at least in Buenos Aires Provincia.
And I agree that cell phone service is spotty. Even in Mar Del Plata, in December, I found that often, in a city of 750,000, I had zero bars on Movistar, walk 5 blocks, and I had reception.
Remember, Spain also gets tens of millions of euros of EU grants for things like roads.
The big difference to me, is not corruption or incompetence, but tax base, (again, 1/3 per capita) and the difference in size and distances. Its easy to drive for an hour on many Rutas in Argentina and see no towns, no buildings. Not so in Spain.
I find roads in Uruguay are pretty similar to Argentina- a few big roads are decent, smaller roads are rough, and the vast majority of roads are merely graded dirt roads.