Or watch this video and level-up your Excel! https://www.youtube.com/watch?v=YNuC6ayrNKQ
Note: Joel Spolsky (co-founder of Stack Overflow, Trello, FogBugz, more) was a program manager for Excel in 90's.
However, for my writing (fanfiction), desktop Office is a necessity. I used to think the "web layout" in Word was weird, but I live by it now. It's a much more efficient use of screen real estate than "print layout" (I have a 4k monitor and like to maximize the window), and Google Docs has no equivalent.
But ignoring the page layout, let's consider something more concrete: loading times.
I loaded a 106 page document in Google Docs on my desktop (AMD R7-1700, 64 GB RAM, NVME SSD, symmetric gigabit internet - a pretty good system overall). It took 27.72 seconds to load, and a couple more after that until I could type without it hitching. According to Chrome's task manager, the tab is already consuming 418 MB of RAM.
On my laptop (Intel i5-6300U, 8 GB RAM, SSD, same internet, Office 365 build 2109), I loaded two Word documents at the same time. Combined, they total 764 pages in print layout. It took 9.71 seconds to load both and for me to be able to type in the 527 page document without any noticeable lag. Word is currently sipping just 250 MB of RAM (and I have never seen it go >500 MB before except when exiting...meanwhile, a single Chrome tab hitting >1 GB is not exactly unusual if my desktop has been running for more than a week).
This doesn't even consider the experience of writing a document this long. Google Docs is already noticeably slower than Word with just a 106 page document, and it gets worse with longer ones. And the grammar checking in Word is miles ahead of what Google has.
Word certainly isn't perfect (I have plenty of complaints about it, and have found bugs which only turn up in long documents), but it remains my tool of choice because Google Docs really can't compete for this use-case. And I know I'm not the only writer in this situation.
Good compatibility with OOXML is extremely difficult. The specification is enormous, hard to understand and, even if you implement the specification, you have no guarantee that you'll get good compatibility with MSO documents.
Considering that .doc is an older, simpler and had been frozen for a long time, maybe its compatibility is better. I'll try asking people that send me OOXML to convert it .doc the next time to see how better it is compatibility-wise.
1. Half of the time people use a word processor, they don't actually need one (plain text would be find)
2. When people really need to format something for print, word processors do a shitty job anyway