You can do this yourself with the Sims 4 Studio. Go to My CC which will show your entire mods folder. Then click on the file you want to change, and options will pop up on the right. Then scroll all the way down and unselect "Allow for random", click "Apply to all swatches" and save. It wont take it off people that currently have it, but it will stop new townies from having it. I have to do it all the time when I download certain outfits. I do agree creators should have it disallowed by default.
Also, Nisa hasn't posted an update yet, and you know WP breaks when WW is updated, so be aware of that.