In short, El Salvador is punished for continuing to take BTC as legal tender which IMF cancelled the $150M trust fund for the country. This kind of actin against El Salvador can be nothing to them as its just $150M, it will not really hurt them that much but its sort of financial penalty to the country. But this is not new.
Read the article once more.
The IMF didn't cancel anything, one of their requirement for approving the 1.3 billion loan (which Bukele begs for a year already) is to drop the 150m trust funds that is used by Salvador for its currency conversions and move that amount to the treasurer as currency reserves.
The thing is pretty simple and all the drama has an easy solution!
If Bukele and his government think that IMF is so evil, why are they still begging them for a 1.3 billion loan?
If you don't like the IMF then don't try to get a loan from them and they will have nothing to ask you.
Simple!