So this "updates" folder recently appeared, and I tried to filter a lot of messages into it, but it only works for a second before all of those types of messages go back into "primary". I'm irritated because recently more types of messages (like political ones I subscribe to or Pinterest things) are going straight to my primary folder. What do I do?
Try selecting the unwanted emails in your primary folder and dragging them to the updates folder. Gmail will send any other emails from the same sender into the updates folder and similar emails will also end up in the updates folder.