Word first? Not quite.
@ Terry Bernstein: "The reality, Microsoft haters notwithstanding, is that Word was the first generally available WYSIWYG word processor and there's an awfully big pool of users."
Word Perfect preceded a decent Word by a long shot, as did Amí Pro and a few others. Word, in the Windows 3 and Win95 eras was a joke compared to the top wysiwyg word processors.
That a restricted/crippled version was bundled with the OS gave rise to a familiarity with the product and bred a certain customer loyalty among those that didn't know how much better they could have had. Once a tipping point was reached for format lock-in, the other word processors were dead.