There are all sorts of motivating factors behind what you say is the failure of Bitcoin in El Salvador. Firstly, the government tried to hurry the process along by basically forcing El Salvadorean's to fund a purchase of Bitcoin (through taxes) which was then given back to every citizen - basically just a vote buying attempt. A slower roll out, which focused on setting businesses up to process payments through Bitcoin in a really efficient way, would have been the correct way to do it or even focusing on the "send money from overseas and avoid excessive middleman fees" would have been a stronger angle to take on this. However some people in the country struggle to find work or even eat, so they're not too interested in this inanimate internet currency when they already have existing payment facilities.