Earlier quoted context omitted.
With Excel its: Do you know arrays, UDFs, Solver, lookups, mastery over chart design, and cell formatting. With word it's basically: Can you do a mail merge and a table of contents? Congrats. You're an expert.
No. There is such a thing as proficiency in word processing. Most people don't use styles, or use them improperly, or modify every instance randomly. They use forced line breaks to adjust page breaks because they don't know about forced page breaks, or the "keep with next" paragraph setting. They've never heard of non-breaking space. They align numbers with spaces. They don't know that you can (and should) have accen…
I mean, for white collar work this is the equivalent of making sure someone knows how to use a semi-colon. It's a "skill" in scarequotes because basic proficiency is assumed and 99% of the time you don't need things to be pixel perfect and if you do you can figure it out on the fly.
Compare these things to, say, knowing when and how to use Excel Solver to give a non-inferior solution set. Or fiddling around to integrate remote data feeds into a sheet for daily automation.