If you are a heavy YouTube user like me, this tool is invaluable. It allows you to organize subscriptions on YouTube into categories. Although it does lack a feature of having a separate "feed" for each category, it's better than nothing. It's super simple to setup and looks like this when you have it working.
I guess that is just Google, why innovate when you can remove stuff for no reason and call it a feature. I think they said something about giving YouTube a cleaner look or something at the time or some bs.
THANK YOU! For years I've been perplexed that this isn't standard. You've just made my life a bit easier! Another thing is, how to manage a playlist with 1000+ videos. Got a handy plugin for that?