I don't doubt that it is true. There was already a thread about the president said to be pro-Bitcoin. By the way, was it finally true ?
According to the presidents Facebook page, the president was very interested in the talk as Branson, plus entrepreneur in areas related to new technologies, such as space flight and use bitcoin is entrepreneurial in humanitarian issues.
Argentina's capital controls and huge corruption sector of the economy is making billions. I doubt they will let their privileges go that easy. The president just said Branson's talk was interesting and it wasn't just about bitcoin.