I thought unsubscribing from legitimate mailing lists was already pretty easy, but Google decided that one step was still one too many. The usability focus these guy extrude is mind-blowing at times.
If you’re curious, that “Learn more” link heads to a Gmail Help article. It just discusses why they did it, and nothing about how. So it’s less than helpful if you run a mailing list and are looking to leverage this feature for yourself. If anyone finds out how to tap into it, please comment or email me.