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 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.
I remember feeling that in English, acronyms are barely used..
It took me a couple comments before that realization though.
Since my client is coming up on a SAP R/3 to S/4 transition, which is due to complete by 2027 (a real timeline), I have informed my dear colleague, a SAP enterprise architect, of a much simpler way forward that you have suggested. Sadly and disappointingly, my colleague architect has launched into rumbling and mumbling about the business transformation being more important than the technology transition. Outrageous and completely unheard of.