Yes, they do, if they want a nice-looking letter.
But...
Excuse while I roll on the floor laughing.
Microsoft might want us to _think_ Word is a DTP, but it's anything but. It's an excellent word processor that has been tarted up with features that give the illusion -- to the ignorant -- that it's suitable for DTP.
I cut my DTP teeth with the "original" Ventura Publisher, versions 2 and 3, almost 20 years ago. Those "primitive" versions, which ran under GEM (Graphics Environment Manager) utterly and totally blow away the current versions of Word (and, I assume, WP and other word processors) for producing long, complex documents. * And they're actually easier to use, because they give you direct control over what you're doing, rather than automating it.
Word has major flaws that make it virtually useless for complex documents, and even for a lot of simple ones. The worst of these is its unstable image placement. You cannot insert an image, then expect it to either remain where you put it, or move the way you want with the text flow. Last year I spent several hours in a largely unsuccessful attempt to organize the graphics in a co-worker's document. Once I got it "right", adding text or new images caused the exisiting images to irrationally shift position, which then required starting over.
Another problem is that, though Word can create TOCs pretty much by the user saying "Put a TOC here", TOC formatting is unstable, and often requires manual alterations to make the TOC look the way you want.
No one at Microsoft seems to care about these problems. And they're not new -- I was complaining about some of them over a decade ago. For example, there's a bug that causes Word to spontaneously switch to automatic repagination for no obvious reason. This bug has persisted across the last four or five versions.
It might sound paradoxical, but in making products "easy" to use, software developers often make them harder to use -- at least if you're the sort of person who cares about what they're doing, and is willing to make the effort to learn. For example, in Ventura you have to manually insert an anchor for each image. In exchange for that bit of work, you can choose how the image will flow with the text -- and it _will_ flow correctly. Word's "automatic" image-anchoring feature is not only much less flexible, but it's confusing to use -- and doesn't work correctly, anyway.
your own
I write for a living. Write is a near-featureless program that _might_ be suitable for plain letters, but is pretty much useless for anything other than very plain text. No one in their "write" mind would use Write to write letters. It's a clunky, slow, poorly designed piece of software.
Word can produce handsome, attractive documents -- if you know how to use it. Most people don't. They write as if the computer were a typewriter, rather than using styles for formatting. The result is ugly, hard-to-edit documents. (Yes, I've had to clean them up. It's appalling.) If you use Word (or any other good word processor) the way it's supposed to be used, you have no need or use for Write. **
I depend on Word for non-complex documents, and it doesn't let me down. I have a 120K-word unpublished novel created with Word. I could convert it -- in a just a few minutes -- to whatever page-layout and typographic format a publisher wanted.
There is a paradox. In general, software with a shallow learning curve (that is, that takes a while to learn) *** is often easier to use, because the slow learning process is the result of the program letting you do what you want to do -- you don't have to fight the program's "automation" -- or the fact that the designer didn't anticipate the particular way you want to do something. A good example is Ventura's TOC and index formatting. They take a bit of time to become familiar with, but you can achieve pretty much anything you want. And TOC and indexing creation is bug-free and stable.
- By complex, I mean multi-chapter documents with complex tables of contents and indexes, tables and cross-references, and flexibly-but-stably-anchored images, with virtually any formatting the user wants. Such documents are difficult to do in Word, but are a snap in Ventura.