I'm sure ODT works well for many personal use cases, but can guarantee it will never see adoption in the legal industry. Microsoft Word is the only viable option for lawyers.
The legal industry also uses MD5 to certify digital evidence hasn't been tampered with, that too will eventually bite them in the ass.
I've seen too many things that seemed to be around forever eventually disappear to believe in the permanence of Word.
I'm a lawyer, though I'm practicing in a wholly different legal system (Romanic civil law) and another country. Why would you say that?
No issues against .docx and and Word per se, but I hate that stupid ribbon with undying hatred. Thus I use LibreOffice as much as I can, while maintaining a licensed Office 365 setup under dual boot with Windows for cases when I have no other choice.
For a similar reason, faxes will never die out in the US, because the legal industry requires them.
That was my hunch, too. Okay, but which features, that only are in Word but not on other products?