I use Word and also have to deal with LibreOffice documents. Both drive me to distraction on occasion but LibreOffice more often. At least Word doesn't insert page breaks and lots of new paragraphs within footnotes when saving to .doc (as needed for Amazon to convert to Kindle.) Word occasionally puts footnotes on the wrong page in a complex document - but then oddly enough, so does LibreOffice.
I am much in favour of creative writing being done in plain text but it's necessary to identify formats such as quoted blocks and subheadings so they can be preserved in subsequent formatting. Not always so easy, and in a long book I'd prefer to avoid doing it by hand.