It was useful on systems with no proper word processor installed. You don't necessarily want to install an office suite for a quick edit.
Plus it preserves formatting better than word. When copying text to and from web pages.
Yeah, lets be fair. Office is expensive, and there is no way in hell I am ever going to subscribe to any software or create a Microsoft Account.
Even the latest traditional non-subscription Office releases seem to require being associated with a Microsoft account, and quite frankly, that will never happen for me. Never creating an online account for what should be offline software. Not in this life, or the next. I can't control what work IT does, but for anything personal? Over my dead body.
Sometimes you have to draw red lines. This is mine. I
will die on this hill if I have to.
Forcing the issue, robbing people of their freedoms bit by bit, but doing it slowly so they get used to it will never work on me. It may work on others, but this is something I personally will
never put up with or accept.
So, Wordpad was a nice light option to have if you needed it.
You can still install something free like LibreOffice though.