Microsoft's specification has previously caused problems for other vendors like LibreOffice's The Document Foundation (TDF) too. There is some controversial history behind this feud between the two formats

No, there was no feud. What happened is that when Microsoft had to create an open document format that everyone could use, they purposefully made their format impossible to implement by anyone. IIRC, The open doc forma spec does it all and is 1500 pages large, whereas the Microsoft format doc is well over 6000 pages long and contains closed parts still anyways.

This is just standard Microsoft strategy and it worked again and dumb fucks again decided to stay married to Microsoft Microsoft because at apparently they love being abused