@Meeker-Morgan it’s rules made that might break things and cause issues. It’s as they said, experimental. Usually not good to turn on settings if you don’t know what they do. You can see the open Github for it below:
But yeah, it’s basically where they’ll put code for things when trying to adjust to YouTube changes or other things. Overall likely won’t notice any difference, but on occasion you may see things tested that will prevent you from accessing content or that allows ads through. It’s a “use at your own risk” as a guinea pig type of thing. People should probably have disabled overall if they want to just use what’s been confirmed to work and is most reliable. But if you’re wanting “early access” to things as they test it, can enable it for those early filter adjustments.