You can’t reason with racism. They believe he was essentially an Arab, and that is the source of his violence. Also, his race makes him unworthy to attack white Christians no matter how “righteous” the motive.
It’s kinda like the Daniel Penny vs. Luigi Mangioni dynamic. Murder is not wrong per se, just who has station and authority to kill whom.
Because I’m not allowed to read the article to know if this is mentioned: a big reason why this would aggravate Wukong fans is that Nintendo is a Japanese company.