That's a whole lot of opinions just to say 'hey, you forgot these office suites were EU and existed for quite a while so we think the terminology you're using is confusing, and we don't agree about using that format as a default'. Seems pretty straight forward and I think I agree. Implementing a popup explaining and then presenting the choice for formats might be a cool middle ground.

But EU-Office is not trying to do a hostile takeover of LibreOffice as far as I know, and having a well maintained fork could lead to mutual benefits. I don't really get the hostility, if it's FOSS, it's FOSS.