I know the length at which IMF has gone to discourage countries who are interested in setting up a bitcoin reserve just because they want to give them loan. I will not surprised if IMF is only making a propaganda on El Salvador regular bitcoin purchase because they are against countries relying on bitcoin to boost their economy in future. They are centralized giving out loans with fiat, do you want them to support to a decentralized system.
The IMF has protect itself as well because it's the money that came from them which EL Salvador has used in buying Bitcoin.
In a sense of being on the part and side of El Salvador because they're bitcoin friendly, the IMF also has the rights to say what they want to say and how their money should be used as per their rules of loaning.
But right now, they can't do anything on it anymore or maybe there's a payment arrangement that the El Salvador is being reminded by the IMF through this kind of statements.