I guess the keywords here are "state-backed Bitcoin buys." El Salvador has ceased buying Bitcoin using government's budget. That's one of the conditions set by IMF when they requested a loan, to which El Salvador agreed.

However, that doesn't necessarily mean the country stopped buying Bitcoin. That doesn't even mean the IMF is preventing the country from stacking Sats. What the loan agreement with the IMF prevented El Salvador from doing is buying Bitcoin using the country's fiscal accounts.

Of course, the country can fund certain programs outside the government's budget.