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:
...
Besides, Germany was the first to recognise Bitcoin as private money and later as legal tender.
Those articles are not accurate.
Japanese law only makes it legal to use cryptocurrencies for payment. It does not require anyone to accept cryptocurrencies.
Germany declared Bitcoin as a "unit of account" and "private money", but not as "legal tender".
I guess it comes down to your definition of "legal tender". In the U.S., "legal tender" means it must be accepted for payments of debt, taxes, and dues. In El Salvador, not only is Bitcoin "legal tender" by that definition, but it must also be accepted for payments (when possible).