My wife and I have had six books published (Wiley and two smaller presses), and the publishers uniformly want Word documents. My wife learned on WP, adored it, and wrote several unpublished novels using it. But when she’d submit the files electronically, agents and publishers wanted Word versions.
We both fortunately have old versions from 2008, and nobody we’ve encountered demanded anything more updated. Thankfully, .docx files are uniform. Editors make use of the Comment feature a lot, which is a big reason they insist on Word. It’s how they mark manuscripts up for changes during author review.
So, love it or hate it, Word owns the world if you are submitting for publication (unless you are just going to self-publish with Lulu or CreateSpace, in which case, you have more leeway).
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My Father-in-law has published several books and his publishers would only accept Apple, so he went to word perfect and exported to PDF which easily can be converted to Apple’s format.
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