The sliders here provide the functionality of changing the values, and a visual aid to give you a better sense of how the traffic is being split.
We wanted to do the math for the user, and prevent the sum to be different than 100%, so we update all sliders on a valueChange. With that and when you have 5+ branches, it can be problematic, so we added a locking mechanism.
I'm attaching a higher res GIF and in the spirit of Dribbble, I'm sharing a very much broken and work in progress Framer link that started this whole feature internally.
Learn more from the announcement.