Back then I read an article about how M$ is crippling the ability of other office packets to read their docx and xslx formats which are supposed to be open formats, but in reality are written in a way never to be fully integrated by competing products. More information about their pseudo open standard: https://fsfe.org/activities/msooxml/msooxml.en.html
Munich in the past have used Linux PCs for quite some time until eventually switching back to windows. Back then they were citing the same incompatibilities to open and read and display M$ office files correctly. So Microsoft is definitely abusing their position as a market leader and trying to cripple competition as much as they can.
So fine them and require all governemtn documents and legal documents of anybkind to be in a true open format. Its only a compatibility problem if people continue to use their format.
That's unlikely to happen in every country where they're popular. Microsoft can just be like "oh you're gonna fine us? We'll pull out and you guys will be completely fucked. Have fun!"
They got into the enterprise sector so early that most offices wouldn't function without Microsoft products/support.