I don't think TRAs will start aiming for 4chan. Many TIMs are incredibly racist (i.e. Yaniv) and love degenerate porn. Those are all things 4chan provides.

I saw a post on the Keffals subreddit saying that they are going for Ovarit and lolcow.farm next, both of which have a heavy female population. TRAs hate it when biological women create spaces for themselves where they can speak freely.

https://www.reddit.com/r/keffals/comments/x58dk9/now_that_kiwifarms_is_down_we_should_take_down/