So your basis for saying "one of the best word processing products at the time." is that a different company made a different product inspired by it (and WordPerfect)? I don't think that is a persuasive argument.
If you said MacWrite was an innovative word processor, I would not have replied. Most innovative is not always the best product at the time.
I am the actual OP. If you're concerned by my use of the word "best", please replace that word with "innovative for consumers". If you have an issue with this new wording, then we'll have to agree to disagree.
While MacWrite may or may not have been "niche" as you said, it most definitely heavily influenced another "niche" word processor available today: Microsoft Word. Word for Mac (1985) was the first graphical version of Word and it was heavily inspired by MacWrite.
If you said MacWrite was an innovative word processor, I would not have replied. Most innovative is not always the best product at the time.