I looked into it, and that passage was actually from the very first revision of the article, added on 28th of May, 2008.
Originally, The Protagonist article was named The "Silent" Protagonist, and was until after Saints Row 2 came out, although there are still a few pages which use that wording, and as you can see by clicking that link, the redirect itself wasn't deleted until this year.
So, the point of it was simply that that's how the wiki referred to the character at the time - even though he did speak in that mission - and no-one has bothered to reword it until now.
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