U.S.A.
The land of acronyms...
Source: I'm from Germany
There's even a small Twitter trend of posting "when you need English to navigate in Moscow". Se. e.g. https://demotos.ru/sites/default/files/caricatures/2019-10-3...
I remember feeling that in English, acronyms are barely used..
I believe you have that inverted.
An abbreviation is a shortened version of a word or phrase, and encompasses both initialisms and acronyms. An initialism is pronounced one letter at a time.
Acronyms are a separate special case - an abbreviation that is pronounceable as a word unto itself.