This is like if Google was whining someone sent them a JPG instead of a WebP. Not invented here syndrome more than an actual openness complaint.
It's also stupid and self-defeating: The top reason people disregard LibreOffice as an option at work is because people believe it's incompatible with the Office everyone else uses. And it's NOT! But if LibreOffice itself keeps promoting misinformation about its own software, it's going to continue to be obscure in business.
LibreOffice is better software and deserves better marketing than this incredibly dumb claim made above.
No, they haven't. See:
https://fossforce.com/2026/02/why-ooxml-is-not-a-standard-fo...
I mean, ODF has been a standard; what Microsoft uses isn't.
And the biggest problem is by claiming it doesn't handle OOXML well, LibreOffice sabotages its own marketability. This blog is exactly what you write if you want to torpedo LibreOffice's success in the business environment.
You can not like Office or Office's file formats, but it's important to understand that it is table stakes for LibreOffice to promote how well it handles those formats and how safely it can be used as a replacement for Microsoft Office in an environment dominated by it.