That's how it is! This announcement was left for the end of the 2021 Bitcoin Conference with the participation of Jack Mallers.
Among the most impressive that helped me understand why bitcoin will be the currency that will lead the country of El Salvador is this.
At the conference the president of El Salvador makes the announcement.
Actually, this is not correct information. Way Before El Salvador, the first country legally accepting Bitcoin as a legal Tender was actually Japan back in 2016. You guys can check the story here:
https://www.sygna.io/blog/japan-crypto-regulation-history-2014-2020/Besides, Germany was the first to recognise Bitcoin as private money and later as legal tender. Check it out here:
https://bigthink.com/technology-innovation/in-germany-bitcoin-is-now-legal-tender/