I don't think 4chan will raid KF, since 4chan has become too complacent in recent years. However, this split between 4chan and Kiwi Farms is still relevant. For years, 4chan has served as an important entry point to other far right sites, since it's the largest site on the web that allows open racism and anti-semitism. Most far-rightists online start off on /pol/ or some other board, then transition to sites like Kiwi Farms during major happenings or when they get banned from 4chan for glowposting too hard. Since 4chan is strongly pro-loli and pro-free speech, Null's and Kiwi Farms' strong anti-loli stance has effectively closed this pipeline, which has historically been Kiwi Farms' leading source of user growth.
So now where does Kiwi Farms go to find a new reliable source for user growth? The majority of Radfems are anti-racists and will be scared off by the Nigger spam, the wignats and other far-right groups are scared off by Null's misandry and Beauty Parlor, the boomers are scared off by the rampant anti-Semitism and Nazism, anime profile pic Twitter is scared off by their anti-loli stance, zoomers don't use forums, leftists are scared off by the rampant racism and transphobia, and soyteens only want to turn Kiwi Farms into their designated shitting street. There's simply nowhere else to go to replace the ever increasing number of people who are either getting banned from Kiwi Farms or leaving the site due to the constantly increasing purity spiral.