If El Salvador sells their Bitcoins, they will gain that huge profit but I don't think that was in the mind of the President. Therefore, they don't earn that yet.
Well, we could use that example that holding Bitcoin really makes sense but I don't encourage holding forever as we're not making any profit from it.
I doubt the Salvadoran President plans to hold forever, even gold or dollars people don't hold it forever but for a duration, so am guessing the man's timing hasn't yet ripen and that's why he's bend on holding even after a 40% profit has been made. That 40% profit in figures might be a huge profit for you but in his position maybe it's just the starting point since the halving and the bull run is still in the tunnel he would want to make more before taking profits.
Today I read about the news of El Salvador bitcoin hodling
Sometimes back when bitcoin price was that low ($16k) a few investors if not many felt discouraged with a flinching desire to sell in fears that the price might keep getting low and addition to the lies and negative rumors from bitcoin haters about bitcoin falling further low even to zero, these lies made many bitcoin holders to hurriedly sell even at a lost.
That is one of the reason many investors left bitcoin because of speculation. Wrong Speculation has decieved many people and kept them in a stagnating condition of not progressing. The history of Bitcoin has tough many to HODL and never give up. Good things take time to achieve, but due to curiosity of quick wealth is making people to loose there opportunity. Good things take time to achieve so HODling bitcoin for long is only the way to achieve the mistake people have made before. If any body bought Bitcoin and sold due to wrong speculation I think buying now and holding for long is the only way to pay the price of the previous ignorant.
It is very simple holding to make profit in bitcoin investment when you have the knowledge, then patience then the continuous knowledge by continually learning about better strategies to employ (like having multiple income source and emergency funds from savings) to keep hodling for as long as necessary.
Take a critical check, you will observe a lot of persons that sold at that $16k lacked all of the above.